How can I recover an existing file of an document?

So when I opened up a file, it asked me if I wanted to open an already saved file of it, and I accidentally hit the cancel/no button, and now I have no clue how to recover my lost data. What should I do?

(My version of Krita is 3.1.1, by the way. I'm not sure this information will be useful with my case, however.)