Unable to restore with FTP backup data

I am in trouble. Please lend me your wisdom.

I downloaded all the data on the server using FTP software, but when I uploaded the data again, the display was corrupted and no longer displayed correctly.

Also, an error message appears in the header section.
What could be the cause?

I have not touched php.

The problem started when I tried to transfer wordpress from the domain provided by the rental server to my own domain and it failed, so I tried to transfer it back to the original server again using a backup to the state before the domain transfer.

I’m really having a hard time with this and would appreciate any help anyone can give me.

• This topic was modified 7 months, 1 week ago by Steven Stern (sterndata). Reason: title

The page I need help with: [log in to see the link]