I fixed all my previous issues but I'm stuck now.
When I try to connect 2 clients through TURN with simple-peer, 1 connects successfully and the other client isn't able to connect to the relay candidate.
In the webrtc internal logs it gives me a "ICEConnectionStateFailed" error and it can't setup an active connection with the relay candidate. It can't be due to the firewall cause the initiating client does work.