Problem because i didnt save

My problem is that I made some mistakes and that I just want to get back to the status I had 3 hours before. Is there a way like a reset butto or something like that to get to your projekt state you had before?

In the blocks editor you can undo/redo, but that's not supported in the designer yet. We typically recommend making regular backups of your projects and using the Checkpoint feature under the Projects menu to have regular snapshots of your projects.