Scrivener Reverted Back to Old Version - Says It's Up to Date

When I went to open up a project I had been working on, I got a message the project didn’t exist. The backup also wouldn’t open, and it wasn’t on the drop down menu. I rebooted my laptop, (Windows 10 OS). The project appeared. However, I noticed all my setting had gone and the interface looked completely different. It says that its version and is completely up to date. Can anyone please advise? Thanks

That is the latest version of Scrivener 1.

Check, have you both V1 and V3 installed?

Thank you, I’ll try that.