Can't connect, getting certificate error

System is Ubuntu server 16.04.5 running on OpenVZ vps under virtuamin control.

When I attempt to connect with my server, by running Nextcloud- from the command line which is protected by an letsencrypt certificate, that has some issues, it tells me it’s invalid. I say go ahead an accept it anyway but it then says no.

This site can’t be reached
The webpage at might be temporarily down or it may have moved permanently to a new web address.

Also it thows this message on the command line:
QApplication: invalid style override passed, ignoring it.
[25987:26024:1022/] No URLRequestContext for NSS HTTP handler. host:
[25987:26024:1022/] CERT_PKIXVerifyCert for failed err=-8179

Update: I added the PPA and installed nextcloud from there and it works. I hope this beta version doesn’t migrate into the PPA files.