Cable line not accessible inside home

I’m moving 03/16 and need to transfer my service to the new address on that date. Xfinity is aware and has an order to activate it then, and I am told I can plug in my current equipment at the new address. The issue is, the cable is not accessible inside my home. 

I explained this to agents several times. I requested someone come out to run a new line that accessible but they stated they wouldn’t come out until the service was transferred, or they would need to cancel the order and I’d need to request the service be moved the day of 

they are claiming there is a line there, and there is, but it is nowhere to be found inside the home. They directed me to a third party, hello tech, to install the line in an accessible area, at my cost. 

Why would this be at my expense? When can I not have someone from Xfinity just run a new line, and why can no one do so ahead of the move?