ิback office problem

[Andy Chongsatitwatan]

i'd been having a problem with my back office since last friday. I can't really do anything in my back office at all. 

I didn't do anything with the setting but in sudden it unusable. first start of with when i get in my back office and try to click on anything

it will go back to log in page and after that the menu column are all gone i can see only text. 

 

I'd clear cache but it doesn't help try to update the prestashop i can't neither. i'm very frustrating right now don't know what to do and seem

noone can help at all. seem like i gonna have to do it all over again but this time i won't use prestashop again cause the system is pretty bad. 

and i won't recommended anyone to use it too. 

i'd attached the picture of my back office. this's what it look like on my back office. 

[joseantgv]

Check console (Ctrl + Shift +J).

[Andy Chongsatitwatan]

i'd uninstalled prestashop from the server .. and installed 1.7.5 the back end looks seem to be ok but still have some problem everytime when i tried to click on something it will go back to log in page again and again can't really do anything. before i uninstalled the old version i got this problem then the next day the back end turn to be the same as the picture i attached. 

how do i solve this problem? the other website that i'm working on using prestashop also has the same problem. is it from the system? and how do we fix it?