Chirpstack Migration Question: AWS Instance

I’m using RAK2243 Gateway which has pre-installed chirpstack-gateway-bridge, Network server and Application Server, which I’ve been using for quite a while.
Now I want to migrate my Network Server, Application Server to AWS and gateway-bridge will remain in the gateway. I’ve installed Chirpstack on Ubuntu AWS instance, chirpstack-network-server, chirpstack-application-server while my gateway-bridge remains in my RAK2243.

Any idea on how to do this? I’ve modified my aws ubuntu instance to have port 1883, 1700 udp and the 8080 TCP, but I when I added my gateway, it can’t be seen.