Hi adwans
First of all, T3 doesn't have that cache settings. So please kindly check if you have cache enabled in your server side or not (maybe you're enabling cache on Cloudflare, etc...)
Next, in template settings >> try to disable the Optimization settings:
and check again.
If the issue still persists, you can share your site's URL of super admin account, I will try to change in custom.css file and see how it goes.
Regards