Terrible service

I used to love them but they have lost all of my respect for the way that they have handled my car!! Think twice before buying a Nissan if having to use datcentre highway for a service. I took my car in for a service with no problems.... after the service it had an overheating problem with the whole bonnet being extremely hot and a smell. I took it back to Datcentre highway and their manager and a worker looked at it and could not figure it out. The manager took it for a drive and brought it back saying nothing was wrong. They then smelt it and blamed it on a clutch smell and sent me home. I got a call the next day to see if i was happy with my service and I said no, i said i brought the car in with a problem, when there was no problem before the service and you have not solved it. Then what happened was I got caught in heavy traffic and it really overheated putting it into the red zone with smoke coming out of the bonnet which was again extremely hot . So last week Friday I took it in again. The worker on duty took it in and said it is a superfan problem. I was told I cannot take my car home. I then started to complain, for I am a photographer. That had no solution to help me with anything to get me to work or to all of my meetings across the weekend. They were actually very rude about it. This happening to my car was due to their ability to resolve my issue that they had created. They should have sorted my car out the first time and not bullshitted me through it and have not figured it out. I borrowed a friends car for the wedding on Saturday, missed two meetings losing 2 weddings on the Sunday and am still without a car and have not even heard a word from them about my car today still. I am really not impressed and am considering calling the managing director of Nissan to sort this problem out. As on the Friday, there was no manager there or anybody that was allowed to make any decisions. They had all gone away for a long weekend according to the receptionist. !! I hope to here back from you soon! like now! for there is still no one that can answer my questions at centre with me phoning today!