Need help communicating between rak and thingsboard community

if i have set up my rak web ui via
i have downlaoded my matt broker from eclipse adoptium(windows 64 bit version) and the mqtt client i am using is mqtt.fx
i am running my broker and desktop docker to get my thingsboard server up on a remote desktop server[203.x.x.x].
i have pointed my rak web ui to the the mqtt broker address which is the 203.x.x.x.
so i can receive uplink from the rak device to my rak web ui. i have also pointed my rak web ui to the mqtt broker which i have configured with the mqtt client(mqtt.fx)

goal: is to get the device from iot device to rak web ui to thingsboard server

things i don’t quite understand:

  1. how to communicate from rak web ui to mqtt.fx, even though i can see from the logs that the connection is a success i dont see anything that i can subscribe to.

“9430]: mosqConnectCB: Mqtt Connect Success …”

  1. i have finished configuring my mqtt broker(mosquitto)
    but i am not sure why it keeps showing disconnection

  2. how to communicate between the rak web ui and thingsboard. if anyone can help to explain this part a bit, it’ll be great