I followed the instructions for installing Nextcloud as found here:
www digitalocean com/community/tutorials/how-to-install-and-configure-nextcloud-on-ubuntu-18-04
the command to set up a cert was:
sudo nextcloud.enable-https lets-encrypt
I found in my searching that adding renew to the end is supposed to work, but I’m guessing that whatever port issue I was having caused it to try too many times.
As to NCPI, I have no idea. I did a stock install and everything worked. I did do it in my home network where it was set up in a DMZ, but the final location is in a much more locked down environment. Thus my question about ports. I did have 443 open, and everything was working, but I didn’t see anything that said I needed 80 open. I’ve made that change now, and I’m hoping I get out of let’s encrypts jail in a few more days and everything will work, but I don’t know if I have to do the renewal myself, or if I have to stop it checking for a week before I can renew, or what. The certificate thing is a new area for me.