Terrible service from Dell Tech Support

Dell make good products and I am very happy with my Dell laptop issued to me by my employer who buy a number of Dell laptops. That is where it ends. There is a problem with bluetooth on the laptop and Dell Tech Support have undertaken to replace the module. I have been trying to get them to meet up with me since 15th April. (Case # ***) Each time I make an appointment they don't keep it and I have to reschedule. If I give them a place and time to do the service they arrive after the agreed time and I have left already. They fail to reply to emails timeously and I gave up waiting on their phone line after 20 minutes. It has probably been the worst service I have received from any supplier!