openVPN not connecting

[dlane2]

I am a novice at Linux and this one has me stumped...

All of a sudden, openvpn stopped working and no clients could connect. The error that shows in the openvpn.log is -

ovpn-server[8513]: Consider setting groups/curves preference with tls-groups instead of forcing a specific curve with ecdh-curve.

I have searched for answers but could not find anything that worked. I also get the error about pivpn not listening when I issue a pivpn -d command.

:::: Self check ::::
:: [OK] IP forwarding is enabled
:: [OK] Iptables MASQUERADE rule set
:: [OK] Iptables INPUT rule set
:: [OK] Iptables FORWARD rule set
:: [OK] OpenVPN is running
:: [OK] OpenVPN is enabled
(it will automatically start on reboot)
:: [ERR] OpenVPN is not listening, try to restart now? [Y/n]

Answering Y to the question seems to have no effect on the connection status.