Can't seem to actually get a technician out here

I recently signed up for Xfinity and opted to do a self-install. I have compatible equipment, but it turns out none of the coaxial cable lines that reach the perimeter of my house are apparently connected to anything on the far end (cable modem can't sync to any channels). I've been in touch with three different agents in as many days, asking for a technician to be dispatched out here to either connect one of those existing runs or run another one, but I haven't yet been able to get one to actually keep an appointment, it seems. The first time, the agent told me the appointment was scheduled for the next morning. No one showed up, and when I checked my Xfinity app, I noted that it had never actually displayed nor confirmed an appointment (nor did I receive any emails or other messages confirming that an appointment had been made). So, I contacted another agent, who apparently concluded that their system had had a problem booking the appointment because I don't actually have a modem registered with Xfinity yet (which I can't do because I can't physically connect to the service). He apparently registered mine, given the MAC I gave him, and scheduled another appointment. Later that evening, I noticed my Xfinity app still didn't show any appointments, so I contacted a third agent and asked them to confirm that I actually had an appointment booked even though I couldn't see it (I told him about the problems I'd had so far). He confirmed my appointment with the tech team. I might be jumping the gun, but given my experience so far, I'm feeling a bit skeptical as I'm now almost halfway through that supposed appointment time slot, and I haven't had anyone show up nor have I received any calls.

This is getting ridiculous. The sign-up process confirmed my address, so I assume that I can receive Xfinity's service at my address. However, I cannot connect to it because there is currently no coaxial cable that reaches my house that carries the service. I'm getting close to my wits' end on this. Strictly speaking, I'm already paying for a service that I can't use. I have a pretty good mind to just cancel entirely if I get stood up once again once the end of this time slot arrives. I'm also a bit irritated that every customer representative agent I've worked with has taken the time to try to upsell me on some other Xfinity product or service while I can't actually get someone to connect the service I originally signed up for. I also have half a mind to file a couple of official complaints (state and maybe federal) if I can't get this straightened out soon.