General help

I have an issue whenever I add a new user or even update an user's profile.

My Moodle version is 3.2.4

In the detail, whenever I add a new / update user, when I clicked to Create User / Save Profile button, the site was loading too slow, and finally it raised the error: 

However with this error, new user was also created or existing profile was also updated.

I tried to re-copy the script at /user/editadvanced.php by the original scripts again but the issue still exists.

Thanks,

Noat