Received very bad service after I bought a car from them

Received very bad service after I bought a car from them. Waited almost 3 weeks to receive a photo of the vehicle registration papers AND they want me to go and pay for my own license disc AFTER telling me they will sort all of that out with the new number plates. The disc has expired and I'm still waiting for feedback from them. Had to send a follow up after 5 days with no response received. And when they finally respond it was a different message to what the salesman told me.