Charged a "residential trouble call" fee...

My Comcast Business internet went down, I called in to support who ended up telling me that someone from my local office would be calling me within 20 minutes to dispatch a tech to fix the issue. After not receiving a call for over three hours, I called back and spoke with someone who said a tech would be out shortly that it was covered as part of the business class service. The tech showed up, didn't see anything wrong inside, replaced a wire outside, and said it was good to go.

I discovered that I was charged $50 for this. Why? I wasn't told about a fee. Neither of the people I spoke with on the phone, nor the tech that came out mentioned a fee. I feel this is shady and I'd like that fee removed from my bill.

Thanks,

Christopher