diff --git a/controllers/application/academy/middlewares/isHalfRegister.js b/controllers/application/academy/middlewares/isHalfRegister.js
index 823f8c6..72c3ec3 100644
--- a/controllers/application/academy/middlewares/isHalfRegister.js
+++ b/controllers/application/academy/middlewares/isHalfRegister.js
@@ -28,6 +28,7 @@ module.exports = async (req, res, next) => {
     const user = await UserModel.findById(decodedToken.id)
     if (!user.user_name ||
       !user.first_name ||
+      !user.last_name ||
       !user.user_type ||
       !user.password) {
       return res.status(403).send({
diff --git a/controllers/application/academy/middlewares/isRegister.js b/controllers/application/academy/middlewares/isRegister.js
index 516c584..262872b 100644
--- a/controllers/application/academy/middlewares/isRegister.js
+++ b/controllers/application/academy/middlewares/isRegister.js
@@ -26,6 +26,7 @@ module.exports = async (req, res, next) => {
     const user = await UserModel.findById(decodedToken.id)
     if (!user.user_name ||
       !user.first_name ||
+      !user.last_name ||
       !user.password) {
     return res.status(403).send({
       status: 'error',
diff --git a/controllers/application/login/loginWithUserName.js b/controllers/application/login/loginWithUserName.js
index 387388d..ded6b6f 100644
--- a/controllers/application/login/loginWithUserName.js
+++ b/controllers/application/login/loginWithUserName.js
@@ -64,7 +64,7 @@ const loginWithUserName = async (req, res, next) => {
     (!user.password) { step = 'password' } else if
     (!user.first_name) { step = 'first_name' } else if
     (!user.user_type) { step = 'user_type' }
-    if (!user.user_type || user.user_name === null || !user.first_name) {
+    if (!user.user_type || user.user_name === null || !user.first_name || !user.last_name) {
       return res.json({
         message: 'کد تایید صحیح بود',
         token,
diff --git a/controllers/application/login/verifyController.js b/controllers/application/login/verifyController.js
index 5d39c22..1ef37aa 100644
--- a/controllers/application/login/verifyController.js
+++ b/controllers/application/login/verifyController.js
@@ -64,7 +64,7 @@ const verifyUser = async (req, res, next) => {
       (!user.password) { step = 'password' } else if
       (!user.first_name) { step = 'first_name' } else if
       (!user.user_type) { step = 'user_type' } else { step = 'profile_image' }
-      if (!user.user_type || user.user_name === null || !user.first_name) {
+      if (!user.user_type || user.user_name === null || !user.first_name || !user.last_name) {
         return res.json({
           message: 'کد تایید صحیح بود',
           token,
diff --git a/controllers/application/profile/profileController.js b/controllers/application/profile/profileController.js
index 47e8e13..bda10aa 100644
--- a/controllers/application/profile/profileController.js
+++ b/controllers/application/profile/profileController.js
@@ -81,6 +81,7 @@ const getProfile = async (req, res, next) => {
     let isRegister = true
     if (!user.user_name ||
     !user.first_name ||
+    !user.last_name ||
     !user.user_type ||
     !user.national_card_image ||
     !user.password ||
diff --git a/controllers/application/register/userFullNameController.js b/controllers/application/register/userFullNameController.js
index f19cb2c..412a0b8 100644
--- a/controllers/application/register/userFullNameController.js
+++ b/controllers/application/register/userFullNameController.js
@@ -7,6 +7,8 @@ const setUserFullNameValidationRules = () => {
   return [
     check('first_name')
       .notEmpty().withMessage('نام نمی‌تواند خالی باشد'),
+    check('last_name')
+      .notEmpty().withMessage('نام خانوادگی نمی‌تواند خالی باشد')
   ]
 }
 
@@ -33,7 +35,7 @@ const setUserFullName = async (req, res, next) => {
 
     // آپدیت نام کاربری به صورت lowercase
     user.first_name = first_name.trim().toLowerCase()
-    user.last_name = last_name?.trim() ? last_name.trim().toLowerCase() : null
+    user.last_name = last_name.trim().toLowerCase()
     await user.save()
 
     return res.json({
diff --git a/controllers/application/register/usernameController.js b/controllers/application/register/usernameController.js
index 28752c4..0fa941e 100644
--- a/controllers/application/register/usernameController.js
+++ b/controllers/application/register/usernameController.js
@@ -14,7 +14,6 @@ const setUserName = async (req, res, next) => {
       })
     }
 
-    // جستجوی کاربر با شماره موبایل ارسالی
     const user = await UserModel.findOne({ mobile })
     if (!user) {
       return res.status(404).json({
@@ -22,6 +21,7 @@ const setUserName = async (req, res, next) => {
         message: 'کاربری با این شماره موبایل یافت نشد'
       })
     }
+
     const validationError = validateUsername(user_name)
     if (validationError) {
       return res.status(422).json({
@@ -32,7 +32,6 @@ const setUserName = async (req, res, next) => {
 
     const normalizedUserName = user_name.trim().toLowerCase()
 
-    // بررسی تکراری بودن user_name
     const existingUser = await UserModel.findOne({ user_name: { $regex: new RegExp('^' + normalizedUserName + '$', 'i') } })
     if (existingUser && existingUser._id.toString() !== user._id.toString()) {
       const suggestions = await generateUsernameSuggestions(
@@ -47,7 +46,6 @@ const setUserName = async (req, res, next) => {
       })
     }
 
-    // آپدیت نام کاربری به صورت lowercase
     user.user_name = normalizedUserName
     await user.save()
 
diff --git a/middlewares/isHalfRegister.js b/middlewares/isHalfRegister.js
index 823f8c6..72c3ec3 100644
--- a/middlewares/isHalfRegister.js
+++ b/middlewares/isHalfRegister.js
@@ -28,6 +28,7 @@ module.exports = async (req, res, next) => {
     const user = await UserModel.findById(decodedToken.id)
     if (!user.user_name ||
       !user.first_name ||
+      !user.last_name ||
       !user.user_type ||
       !user.password) {
       return res.status(403).send({
diff --git a/middlewares/isRegister.js b/middlewares/isRegister.js
index 516c584..262872b 100644
--- a/middlewares/isRegister.js
+++ b/middlewares/isRegister.js
@@ -26,6 +26,7 @@ module.exports = async (req, res, next) => {
     const user = await UserModel.findById(decodedToken.id)
     if (!user.user_name ||
       !user.first_name ||
+      !user.last_name ||
       !user.password) {
     return res.status(403).send({
       status: 'error',
diff --git a/utils/usernameSuggestions.js b/utils/usernameSuggestions.js
index 92c9833..51e26a7 100644
--- a/utils/usernameSuggestions.js
+++ b/utils/usernameSuggestions.js
@@ -12,79 +12,40 @@ const isUsernameTaken = async (UserModel, userName, excludeUserId) => {
   return true
 }
 
-const splitBaseAndSuffix = (value) => {
-  const match = value.match(/^(.*?)(\d+)$/)
-  if (!match || !match[1]) {
-    return { core: value, suffix: null }
-  }
-  return { core: match[1], suffix: Number.parseInt(match[2], 10) }
+const buildCandidates = (base, attempt) => {
+  const random2 = () => String(Math.floor(Math.random() * 90 + 10))
+  const random3 = () => String(Math.floor(Math.random() * 900 + 100))
+  const random4 = () => String(Math.floor(Math.random() * 9000 + 1000))
+
+  const builders = [
+    () => `${base}_${random2()}`,
+    () => `${base}.${random2()}`,
+    () => `${base}${random3()}`,
+    () => `${base}-${random2()}`,
+    () => `${base}_${random3()}`,
+    () => `${base}${random4()}`,
+  ]
+
+  return builders[attempt % builders.length]()
 }
 
 const trimToMax = (value) =>
   value.length > USERNAME_MAX_LENGTH ? value.slice(0, USERNAME_MAX_LENGTH) : value
 
-/** پیشنهادهای مشابه: amiri2 → amiri3, amiri5, amiiri3, amiri334 */
-const buildCandidates = (base) => {
-  const { core, suffix } = splitBaseAndSuffix(base)
-  const candidates = []
-
-  if (suffix !== null && !Number.isNaN(suffix)) {
-    candidates.push(`${core}${suffix + 1}`)
-    candidates.push(`${core}${suffix + 3}`)
-    candidates.push(`${core}${suffix}${Math.floor(Math.random() * 9 + 1)}`)
-  }
-
-  const numericSuffixes = [3, 5, 7, 12, 21, 34, 99, 334, 567]
-  numericSuffixes.forEach((num) => {
-    candidates.push(`${core}${num}`)
-  })
-
-  for (let i = 1; i < Math.min(core.length, 5); i += 1) {
-    const ch = core[i]
-    if (!ch) continue
-    const doubled = `${core.slice(0, i)}${ch}${core.slice(i)}`
-    candidates.push(`${doubled}${suffix !== null ? suffix + 1 : 3}`)
-    candidates.push(`${doubled}${Math.floor(Math.random() * 90 + 10)}`)
-  }
-
-  candidates.push(`${core}_${suffix !== null ? suffix + 1 : 1}`)
-  candidates.push(`${core}.${Math.floor(Math.random() * 900 + 100)}`)
-  candidates.push(`${core}-${Math.floor(Math.random() * 90 + 10)}`)
-
-  return [...new Set(candidates.map(trimToMax))]
-}
-
-const generateUsernameSuggestions = async (
-  UserModel,
-  baseUsername,
-  excludeUserId,
-  count = 3
-) => {
-  const base = baseUsername.trim().toLowerCase()
+const generateUsernameSuggestions = async (UserModel, baseUserName, excludeUserId) => {
+  const base = trimToMax(baseUserName.trim().toLowerCase())
   const suggestions = []
-  const tried = new Set([base])
+  let attempt = 0
 
-  for (let attempt = 0; attempt < 80 && suggestions.length < count; attempt += 1) {
-    const candidates = buildCandidates(base)
+  while (suggestions.length < 3 && attempt < 30) {
+    const candidate = trimToMax(buildCandidates(base, attempt))
+    attempt += 1
 
-    for (const candidate of candidates) {
-      if (suggestions.length >= count) break
-      if (tried.has(candidate)) continue
-      tried.add(candidate)
-      if (validateUsername(candidate)) continue
+    if (validateUsername(candidate)) continue
+    if (suggestions.includes(candidate)) continue
+    if (await isUsernameTaken(UserModel, candidate, excludeUserId)) continue
 
-      const taken = await isUsernameTaken(UserModel, candidate, excludeUserId)
-      if (!taken) suggestions.push(candidate)
-    }
-
-    if (suggestions.length < count) {
-      const fallback = trimToMax(`${base}${Math.floor(Math.random() * 9000 + 1000)}`)
-      if (!tried.has(fallback) && !validateUsername(fallback)) {
-        tried.add(fallback)
-        const taken = await isUsernameTaken(UserModel, fallback, excludeUserId)
-        if (!taken) suggestions.push(fallback)
-      }
-    }
+    suggestions.push(candidate)
   }
 
   return suggestions
@@ -92,5 +53,4 @@ const generateUsernameSuggestions = async (
 
 module.exports = {
   generateUsernameSuggestions,
-  isUsernameTaken
 }