Connecting gateway to TTN ( Rak5146 + Raspberry PI4)

I have problems with the gateway, it does not connect to the TTN (The Things Network) server. I am using the RAK5146 (based in Semtech SX1303 y SX126X )
Concentrator for LoRaWAN and a raspberry pi 4, I used the quick guide from the official page ( where I bought the concentrator but it seems to not work correctly because the status of the gateway registered in the TTN platform is offline.
Heeeelp me please