I was flying my dji phantom 4 at night and when it woukd get a bit too dark it would say the sensors aren't working and then the gps sign would leave. Does this mean i no longer have gps?

GPS works day and night, in all weather and all over the world.
Your Phantom should have GPS any time it has a good view of the sky.

Did you mean GPS or the Obstacle Avoidance System (OAS) because the forward obstacle sensing cameras do not operate at night or low light, it states that right in the App.

Well it says the OAS is not working because the light is too low and then my gps sign goes off

Sounds like you may live in the dreaded "Twilight Zone"!! ;-)

Sorry, I  was just watching some extremely mysterious YouTube videos... Ha
That is a strange occurrence, all right.

RedHotPoker

Hello classic2003, please try to play back this flight record in DJI Go app. If you see this message, it is appreciated to make a screenshot and post it here.