New customer deceived about installation fee

I am a new customer to xfinity and had to self- set up the internet in my apartment a month ago. I was on the phone with customer service reps before choosing Xfinity and during troubleshooting and the technician service, the xfinity reps said that they 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 30 of the 100 can be waived. Basically the technician messed up and now I am on the hook for the other 70 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 very unhappy and deceived with this customer service. A mistake on their end is now going to cost me 70 dollars. I also found out they charged me for service for days I didn’t not have service. They were willing to take my money without service being provided but did not want to take the full $100 away when they mentioned they would waive it. I’m very disappointed and cannot wait to leave this service. I feel very misled.