在插入正确的登录详细信息（即用户名和密码），php和jquery中的代码后，我的代码登录失败

I have following code (php and jquery) for Login for Student and Teacher (using same form for both access). In my system the admin can create Student and Teacher. Once created, the details are saved into database. The saved details is suppose to be use for login to their admin panel. But, the problem is , when Student or Teacher wants to login with the login details, provided by the admin (which has already been saved in database table), It display error message : Login Failed, Please check your username and password. (Same details, saved into database table is used for login process). This aching my head. If someone can tell me , if there is some error in my code, will be much appreciated.I have following code (php and jquery) for Logi