Love the rating.
Yeah, a warning for the button might be a good idea. I'll see that I add that for next update. Also, there sadly isn't an easy way to "fix" this. Best thing I can offer is to create some sort of reset button for the hamsters in general (something I'll likely do anyway) and to send you a fix for this issue in particular, if you tell me which hamsters it were that you accidentally unlocked. There sadly isn't something as simple as an "undo" button or something like that.