Hi there,
If your “pretty” permalinks aren’t working on your site, I suspect that one of these things can be happening:
1- There is still some permalinks cache that is ignoring your current permalinks structure. Try to save your permalinks structure again in Settings>Permalinks to flush this cache and check if it solves the issue.
2- Your .htaccess doesn’t have enough permissions to let WordPress update it with the wanted structure. If that’s the case, you should receive an error at the bottom of the page indicating that WordPress hasn’t been able to update your .htaccess file and providing you the content that you should manually use there. In this case, try to manually edit it and change its permissions to make sure that WordPress can update it (you can also ask for help to your hosting support team if you have doubts or experience any problems with it).
I hope it helps!