I want to dispute a service charge

I am writing to formally dispute the $100 service charge applied to my account for the recent technician visit. I believe this charge is unjustified based on the circumstances of my installation.

When I signed up for service, I was explicitly informed by Xfinity that my residence was already "pre-wired" for service and that no technician visit was required. I was instructed that the setup process would simply involve plugging in the provided equipment and following the activation steps.

Upon attempting to set up the service, it became clear that the infrastructure was not in place; there was no cable connected from the street to my home. As this is work that I am neither authorized nor able to perform, a technician was required solely to complete the installation that should have been ready at the time of me installing the modem. 

Furthermore, I was charged for this visit despite the fact that the technician's presence was necessitated by an error in Xfinity’s initial service assessment, not by a request for assistance on my part. I did call and tell them that I didn’t have an access line. They said they would send someone out. I told them I’m not paying for that. Plus, the additional internal testing performed by the technician was not something I requested or deemed necessary for the basic connectivity I was promised. 

As a new customer, this experience has been frustrating. I would appreciate it if you could review this charge and get it waived, given that the visit was required due to inaccurate information provided at the point of sale.

Thank you for your time and assistance in resolving this. I look forward to hearing from you.