I did something a bit stupid yesterday... I was playing around with Firewall rules on my Forge server. I setup a rule so that the only place I can SSH into my server was from my home IP Address.
However, as soon as I did that, I realised that I could not longer deploy code or do anything via Forge on that server. Then I realised my mistake.... I blocked Forge's IP Address from SSH'ing to my server.
In case someone else finds them in my position, here are the two commands I ran to fix the issue. Of course, you need to SSH to run them.
sudo ufw allow from 22.214.171.124 to any port 22 sudo ufw allow from 126.96.36.199 to any port 22
ufw under the hood to manage firewall rules so that's what I used to manually give Forge back control. The two IP addresses I listed in those commands link up to the IP addresses from their documentation.