Poor customer service and False advertising

I visited the service department this morning to take up an offer that was advertised on ECR. I got to the branch as soon as they opened this morning only to be told that the offer is no longer valid as they were fully booked. I find this very ********* as the advert did not mention anything about a booking before the 16th Dec 2015.Further to the poor service I was given a booking date of 29th Dec. I was then asked to go outside and record the VIN no. Of my vehicle without any assistance, After getting this information I was asked for my details while standing and not even offered a seat. I must say that my visit to your branch was a horrible experience and is far from the highly rated customer service that you normally offer.