URL of Website Changed by itself

I have a problem with my client’s website. It is from time to time changing its URLs by itself. E.g. we have there a website directly going to /get-started and it for example was changed to /get-started-2.

The same problem occurred in our language version of the website and instead of /users – it changes to the /users-3.

Do you have any idea why it is constantly changing? Because then it is showing coverage issues in GSC as a result.

Thanks a lot for helping and giving advice in advance.