expressions - What does “you dropped them keys” mean?

I was listening a song called To The Left from Beyonce.
There is a part that she sings:
“Because you was untrue
Rolling her around in the car that I bought you
Baby you dropped them keys
Hurry up before your taxi leaves”.

Could you guys explain me what does she mean?
If she was talking about the car keys, it shouldn’t be “you dropped its keys”