update

app/Models/User.php

@@ -203,7 +203,7 @@ class User extends Authenticatable implements Auditable
         // 获取同一天开始的所有课程
         $course = Course::where('start_date', $courseSigns->course->start_date)->orderBy('created_at', 'asc')->get();
         // 获取同一天开始所有课程的报名信息
-        $courseSigns = CourseSign::whereIn('id', function ($query) use ($course) {
+        $courseSignsList = CourseSign::whereIn('id', function ($query) use ($course) {
             $query->from('course_signs')
                 ->where('status', 1)
                 ->whereIn('course_id', $course->pluck('id'))
@@ -212,7 +212,7 @@ class User extends Authenticatable implements Auditable
         })->orderBy('created_at', 'asc')->get();
 
         // 获取当前用户id在$courseSigns中第几位
-        $index = $courseSigns->search(function ($item) use ($user) {
+        $index = $courseSignsList->search(function ($item) use ($user) {
             return $item->user_id == $user->id;
         });
         $no = $prefix . str_pad($index + 1, 3, '0', STR_PAD_LEFT);