Fongo Community Forums

Before you blame your ISP check out this linkhttps://pentest-tools.com/discovery-pro ... line-nmap#. Select the option to enter your own selected port range, enter 5060/5061, answer the simple math question to prove you're 'human' and START. You should receive this as a (partial) result; PORT STATE SERVICE
5060/udp open|filtered sip
5061/udp open|filtered sip-tls

If you do receive that result, it means your firewall is either not configured properly or insecure. Having port 5060 open leaves your equipment vulnerable to hacking. If your VoIP service won't work any other way, then you should set your port number to a high/random number between 20000 and 65535.