Why bill is so high after being told that I was being credited a week

We were having problems with our TVs for months until it got to a place that we could no longer watch TV as the screen pixelated made it impossible to see what was on all the TV screens.

The technician came out to the house as it was determined that there was something at the house causing the issue. It was determined that there was electricity in our cable line. The cable outside was changed, along with the modem for our telephone line. Once that was all set, I did call the electrical company, who came out and fixed the issue with the electricity in the lines. During the initial call I was informed that I will be credited a week of service since we could not use our TVs.

A week or so later I realized that the "C" button on the remote no longer brought up the sports section. Xfinity sent a technician out to the house, never mentioning that we would have to pay for the visit. He came out, removed the modem for the telephone and hooked the telephone up to our cable modem. Apparently the TV was picking up services from the telephone modem that was causing the TV not to function correctly.

We received our bill $432.51! Prior to this bill we would be charged $327.09 a month. What a surprise! I did call customer service, they took off $50. That was a nice gesture, however what I thought would be a bill of $300 for the month--subtracting the week of services I was originally told--was $100 additional for the second technician to come to the house and not subtracting the week of service. 

Why were we charged the the second technician to come to the house when it was something the first technician had changed out that caused our TV remote not to function correctly? I called customer service, they could not help me remotely, which is why a technician had to come to the house.

Being a diamond customer, I would have expected better service regarding the bill then the lip service I received when I called about the bill. I am still upset with xfinity as this has been an ongoing issue for awhile. The original issue with the cable, finally got corrected, for that I am happy. However with fixing that issue, the new telephone modem cause the issue with the Xfinity remote and the TV in the Living room to connect wireless through the telephone modem. 

I would like to be credited the remaining $50 for the second technician and the week of services that I was originally told would happen.