RAK7371 with SX1303 fine timestamp


I’m trying to make the fine timestamp feature work but I’m having some troubles.

I installed everything, enabled finetimestamp in the global_conf, packet forwarder allows it but then the fine timestamp is never send. It always says that PPS history is too short.
The host (a raspberry pi) has a GPS but it seems that has problems with time reference:
I dont know if that could be the problem and I did not find any reference to this.

Any help is welcomed.