Stops working in about a day, works again if reinstalled

This happens with certain hosting providers, but not the others. Clients connect successfully to the server first, for about a day, but then stop. Removing old clients' configurations and adding new clients doesn't help. If you uninstall Wireguard and then install it again following ./wireguard-install.sh prompts, all works again.
Any ideas why something like that can happen and how to fix it? Thanks.