Sim 808 can't connect to GPS

Good morning,
I've got this board: https://www.amazon.it/sviluppo-Antenna-Network-Raspberry-Wishiot/dp/B07Q1B9FKZ.
It can't connect to GPS. GSM works fine but GPS can't lock. I need to get time using GPS.
Any idea?
Thank you.

Are you outdoors or near a window?

Good morning,
I'm near a window. Should I go outdoor?
Thank you.