Web look broken

Hi,

My website look something wrong when install WP Fastest Cache plugin.

My problem is, when I try to login in my website, it look like this

See here >>> https://www.awesomescreenshot.com/image/1585048/05ea0e7018277f01dc3c126aadaedb41

Acctually, it should like this after login

See here >>> https://www.awesomescreenshot.com/image/1585061/391376d3a3f68186ebf2c25f2452b336

And now, I deactivate this plugin and it back to normal.

This is my website >>> https://www.semaniskurma.my/

How to fix this?