Modify server port after configuration

Hello,
I have recently changed the internet provider at home, where I have a nextcloud server running.
One important change with the new one is the port redirection. Now I must use weird numbers for external port, instead of the one I used before. As such, my client is not able to login into the server.
In the computer it was easy after modifying the config file, but, what about the android client?
Is there any possibility to modify the server address and add a different port instead of 443?
My phone is rooted, but I do not know which file to look for.

Thanks in advance.

Hello, is it possible that you have had an fixed IP4 IP-address before and now your ISP switched to IP6? As long as you’re using a DNS or DynDNS name for your server, this should not be a problem. You simply have to update your DNS record with the new IPv6 address.

Regarding portnumbers you should be free to choose your forwarded/redirected ports in your own router/firewall or reverse proxy. Again, this is an issue regarding to your router/firewall/reverse proxy and has nothing to do with Nextloud nor with your ISP.

It is not possible to modify a server address but it is possible to append the port number directly behind the server name, once you delete and re-add an account, e.g.

https://<fqdn>:<port>/...

Hello,

thank you for pointing in that direction, it could be related.
My knowledge on networks is really basic, and this new world around ipv6 it is more complicated.
Indeed I was using before the services of dynu.net to obtain a domain name. In my previous router I had a port mapping of port 443 to internal port 443 to mu local nerwork address server (192.168.1.11)
Now I think the whole thing is about ipv6 and the port mapping is a bit different. The router allows me to write a internal port (443 in this case) and an external one, but when I apply the external port changes to 22345 or something like that.

Anyway, I know this is totally unrelated to nextcloud or the client. I just asked to avoid removing /re-adding the account.

Thank you .