Protect America Repeated charges and no alarm Texas

I order an alarm system over 2 years ago, and I never received the alarm. After they billed me I contacted them to let them know I had not received the alarm, they said they would send a replacement out. They billed my card for 2 more months and I had still not received the alarm. I called to request a refund for the 3 months billed since I had never received or installed or activated the alarm system. I was told they would issue a refund however next month I was billed again. I called again and stated that I still had no alarm and was still being billed I was told they could not cancel my service because I was under contract for an alarm never received or activated.

They offered to send out yet another alarm, I told them I did not want an alarm being monitor by a company that was obviously not competent. I ended the call after being transferred several times by people trying to convince me to give them another chance but I had decided to get a local alarm service that was more money per month but more reliable. They continue to bill my credit card for almost 2 years and to call and harass me non stop several times a week. One of my friends mention I could get my credit card company to block the monthly charges which I did in August. They are not threatening collections, and still calling non stop after being asked repeatedly to stop calling. I have asked for a copy of the signed contract and have not received it.