Problem in WHMCS 8.5.1 Admin Area Menus

[Devilz_hrlp]

Hello,

I am facing a very weird Issue with WHMCS 8.5.1 version. (was working fine till  version 7.10.x)

Please check following Image :

https://i.imgur.com/iZaNmF9.png

Under WHMCS admin Panel , MENU is NOT displayed properly. SETTING link is misplaced and giving a PAIN IN ASS as its making hinderance in clicking  "SYSTEM" tab.
I tried to re-install , made fresh Install but it didn't helped.

Also tried to clear template cache ....... but no use.. Problem still persist.

Please Help me