[Luicy.]

You need the vehicle model, not the ID.

PHP код:

if(GetVehicleModel(vehicleid) == 81) 


You don't need GetVehicleID neither since it's already there.
Enjoy and welcome back.

Edit; My bad, I didn't read clearly.
Use vehicleid, since OnPlayerEnterVehicle is when you press enter and start running to the door.
If you'd like to see the message when you are inside the vehicle, use OnPlayerStateChange.

PHP код:

if(vehicleid == 81)