Ok so the answer is to send the message with netcat, I thought it did not work because of my conduit which bufferised the messages in order to send them later.
First I tried this (I tried to throw the lora message both with tcp request and injection) :
And after that I tried this :
But if i do what you say, how can I know if the device received the message ? I think it will not answer ?
Ok, thanks !