Accidentally deleted a class attribute, now a mess

I accidentally deleted a class attribute while editing my table, and because auto save was set to on, it saved it and now my table looks quite the mess. Is it possible to fix this or do I have to start over from scratch? Edit: Now I made it worse, I changed the template, and now all the data is gone. I didn’t realize changing the template erases the data I inputted :(

See screenshot