Pathetic customer service

I took out a 36 month subscription on 30th June 2023. The advisor called for a scheduled installation for 10th July at 9am. In the 10th July no one pitched up for the installation or not even a call. I called in and was told that someone would call me back after I requested that someone does call me regarding canceling this contract or assistance for installation. No surprise, no one called me back. Friday 21st July I called the customer care, explaining my annoyance, I was transferred to scheduling, scheduling then transferred me to sales, Sales wanted to transfer me back to scheduling. At this point I was absolutely irritated, more so at the lady who did not even give me a chance to explain, nor want to give me her name. She rudely shouted and dropped the call. I called back highly frustrated and asked for a manager or supervisor, I spoke to a gentleman who assured me that he would call me back regarding this situation. Again no surprise as I'm yet to receive a call. Can someone assist with canceling this contract since I cannot deal with such disregard and disrespect for clients time and money.