A common query on the forums relates to port forwarding or an inability to connect to a Nextcloud server from outside the local network.
Before raising a support topic, it’s a good idea to determine if the relevant ports are open on your router. To check this, visit:
http://www.yougetsignal.com/tools/open-ports/
Input your IP/Hostname and the port you wish to check.
If it’s not successful you’ll need to double check your network configuration. If it is, the issue may lie elsewhere and creating a support topic with as much information about your environment as you can provide will help troubleshoot the underlying fault.