Invalid gps time reference (age: 1639220977 sec)

I have built a lorawan gateway using a Pi Supply IoT Gateway HAT (RAK833) and added a GPS nano 6 module. I have used balenacloud to install the OS.

The Gateway is registered on TTN and the connection os working fine. I have placed a GPS antenna out of the window, but the gateway is not getting coordinates.

This is what I see on the balena console log:

main ### [GPS] ###
main # Invalid gps time reference (age: 1639221007 sec)
main # no valid GPS coordinates available yet

I am a bit lost here, how can I fix this in order to get coordinates?

Can someone please advise?