Incorrect charged by COX

I'm a new member to COX and I have just moved to my new apartment since Aug 04th 2020. However, on July 17th 2020, I registered the COX services with COX representative recommended by my apartment and they already charged me at the time of calling, even that I would not use it until my lease started. It just doesn't make sense to me! I was charged for the period of time I didn't start using it? I tried to contact COX multiple times and they seemed all avoid this problem! How could I resolve it?