Bought a 2000 polo gti in October and everything spot on with car except remote won't open car only when key in lock manually also interior light doesn't work when door opens but works otherwise any help would be appreciated 

First Welcome to the forum.

 

The interior light will probably be the switch in the door frame, they are a dual circuit switch, one for the interior light, the other for the speedo ( lights ON warning) & fuel pump priming when the door opens.

 

The central locking, could be flat battery in key fob or the fob has lost it's pairing with the car, there are youtube videos on how to re-pair the fob to the car