[Error Message] Internal 400 error occured when changing avatar,

[Noris]

Why i'm having internal 400 error after clicking "change avatar" button then the avatar wont change?

im using a free host. never had any issues except this.

its integrated with cloudflare.

default avatar dimension : 140x135
max avatar dimension: 140x135

some random errors

MyBB SQL Error
MyBB has experienced an internal SQL error and cannot continue.

SQL Error:
2013 - Lost connection to MySQL server during query
Query:
UPDATE mybb_users SET `avatar`='./uploads/avatars/avatar_1.jpg?dateline=1481038223', `avatardimensions`='120|123', `avatartype`='upload' WHERE uid='1'