Massively bad service from mercedes grand central

Im very unhappy with the treatment we received from mercedes at grand central, particular Eric the service manager and their booking clerck Sheryl. The other day the broke in my car and smashed the window now the glasses fell in between the door, glasfit managed to fix my window and they were so kind to get my insurance to approve that Mercedes can assist in taking out the excess glasses that fell inside the door and glasfit also assisted me in making the booking, through an email which i was also part of. This morning as the car was brought in , Eric told my partner we have to pay for the repair, where as the glasfit personel did mention on the email that they have an account with mercedes they must charge there, but Eric insisted we need to pay, i tried to see if i can talk to him ,he was not interested.secondly we were not told the car was gonna be booked the whole day since all they had to do was to remove the glasses and let us go, now we are told we can only get the car later as in we brought the car for service, bad treatment, Thirdly because now we realise we have to fetch the car later we ask for a shuttle and we were rudely told we were suppose to book it ahead, where as when we book with Sheryl she never mentioned anything to me on the email that i need to book ahead imagine on this rainy day my partner is standing in the rain, they never even offered him to sit in the cafeteria to wait there since they will be busy with the car longer than we anticipated. Other than everything Eric handled the whole situation in a very rude and harsh way. For service manager im not happy. All the mercedes i have been, we have never been treated the way mercedes in grand central did.Now for the fact that i complained eric decided to cancel the service they had to give us, who does that.are we not suppose to complain when we are not happy.