No ACKs on node

Hello Everyone

Im struggling with what I think is a setup issue.

My node joins, sends a tx and gets an ack.
After that it never receives another ack if I tx again (I am asking for acks).
The chirpstack web frontend on port 8080 see the packets and labels them as confirmed data up, but the node never receives an ack after the initial ack when it first joins and sends a packet.

Im running the latest chirpstack docker container on a ubuntu 18.04 server.
Im using vernemq as my mqtt broker, i’ve added the necessary credentials to the chirpstack config files.
I’ve also allowed all the users on vernemq (chirpstack app , network server etc) to write / read to any all topics

Everything else in my setup works fine except I cannot get acks on my node.

Can anyone assist me here and share some light on this?

Thanks
Nathan