Clients can not connect after change ip of server

[fpgi]

Hi some datacenter have this ability to change ip of server like Hetzner after change ip and start server , my clients can not connect to server i change /etc/openvpn/server/server.conf ( i think it is exact file of openvpn configuration ) and change config file of user but still can not connect . i must uninstall openvpn via script and install that again and after that it work . which files must change for successful connection of user after change ip ?

[Nyr]

In Debian/Ubuntu: systemctl stop openvpn-iptables.service

Then, edit the /etc/systemd/system/openvpn-iptables.service file and change references to your IP address.

And start again with: systemctl start openvpn-iptables.service

For RHEL-based distros you would need to edit the firewalld rules.