All my old files that went missing suddenly showed up but the I had started since the purge disappeared Is there a way to find it
This may not be the reason, there may have been some sort of issue with the server but…
What this sounds like is you had signed in with a different email address and found your files gone, you made a new model with that account.
Then you signed in using the previous email which would show you your original files but not the new one.
If this is the case you would need to sign in with the other email to find the new file, use download to move it to you computer, then open it with the original email.