Port 53 Forwarding.

I made a port 53 forwarding from my firewall to my internal DNS Bind
server. However when I tested from outside firewall with dig tool it didnt
work. The same command works inside the network, which confirms the DNS
Bind Server is working accordingly.

Now my question is, is ISC Bind server users Port 53 or other? I didnt
change anything while install Bind and Does it use UDP or TCP?

Appreciate any help.

Thank you

Sam.