Help all code disappeared and UI blank :/

Hey could someone help me. I’m not sure what happened but I’ve now got an error message on my screen that states ’ Old versions are read-only. Restore or switch to latest to edit’

The restore is there but not responding.

In addition all code is gone and UI is blank??

That banner appears when you’ve selected a previous version

To get the chat sidebar back, click the double arrows to re-expand it