I Need A Technican To Replace A Cable From Its Connection Inside Our Condominium, To Inside Our Unit.

My name is [Edited: "Personal Information"] esq. [Edited: "Personal Information"], [Edited: "Personal Information"].my address is [Edited: "Personal Information"]. I live in the penthouse. The condo at this address has an agreement with xfinity to provide cable service for the building. In the penthouse i have upgraded speed and xfinity extenders which according to xfinity give me an outstanding wireless signal.  The problem is that the cable connection from the utility room on the 7th floor (excellent signal to this point) to the penthouse, less than 10 feet away is old and degraded. Xfinity techs have identified the problem but will not install a new cable. The condo says that this is xfinity's problem to fix. My tv picture flickers off every few minutes due to the bad cable. I spend over $400 a month with xfinity for mobile, tv, internet, landline and watches and can not watch tv. [Edited: All Caps]