Professional Install Dispute

I am a new customer to xfinity and had to set up the internet in a house I just purchased. I was on the phone with a technician for several hours and unable to hook it up ourselfs. The xfinity rep said that they would schedule a professional installation and that he would waive the 100 dollar fee. I just got that first bill and the 100 dollar fee is not waived. I called customer service and the technician did not notate that the fee was to be waived on the call. So the customer service said that only 50 of the 100 can be waived. Basically the technician messed up and now I am on the hook for the other 50 dollars. Not believeing me that the technicaian said the entireity was to be waived. I asked and they said there was nothing more I could do and their hands were tied. This is why so many people are unhappy with this customer service. A mistake on their end is now going to cost me 50 dollars. I cannot not wait until my 2 years of contract is up so I can switch to a provider will honor their word.