Port Forward for hosting a minecraft server.

I have recently set up a minecraft server to run on a spare laptop, I have done everything for that correct (confirmed because I can connect to the server locally), but I am unable to have friends connect across internet.

I have set up the port forward through the Xfinity app on port 25565, and double checked it is open on my external IP address. I have tried having both myself, and my friends completely disable firewalls in an attempt to resolve this, (even though we have all made rules to allow the connections) but this has not fixed the issue.

I am wondering if anyone has had any experience using the Xfinity gateway/modem combo to host a server, or if Xfinity for some reason is blocking this for a reason I do not know?

Any help would be appreciated, thanks.