im not sure this is the first letter i have had from the court

I have recieved an attachment of earnings for a car i owned when i took the car on i had a few insurance policies on it which i phoned and told them to cancel i also wrote to them asking them to cancel them they did not and i could not afford the car at the time (sickness at work = less pay) as the payments were to high with these on they said i had 14 days to clear the balance which i was going to clear as i was back working then 7 days after the letter i get a bailiff knocking on a sunday night demanding the car back i have heard nothing from them until i got this attatchment of earnings asking for £8500