Create the file again with the exact same name by clicking New File (Image here) and typing in the correct name. Then, click the history button at the bottom right corner (Image here) and use the arrow buttons/slider to go to the version just before the file was deleted (should be the version before the current one). Click the restore to here button. Voila! Your file will now be restored.

One additional thing,
You seem to think that you are talking to official Replit support. This is actually a user-to-user Q&A site. It's not your fault. :)