Raffles Private Hire Ltd in Milton Keynes

I pre booked a taxi the night before I needed it and for 4.30am on the following morning.
At the specified time of collection there was no sign of my taxi so I rang control only to be told there were no cars in my area, bearing in mind I live in the same area as this firm is based.
How can they not have a car in my area when 1, they are based in Milton Keynes and 2, I had pre booked the night before! Poor customer service :(