Hello there @Zeebeoy!
That is very unfortunate, your maps were most likely stored locally only; since the re-downloads are empty, the content was not pushed or checked-in with revision control.
Depending on the way your machine was reset, it could be possible to retrieve part of the data with external tool, like Recuva or Disk Drill. Give it a try, if possible.
For the future, I would recommend getting familiar with revision control, and the best practices around it: