Every promise broken and substandard customer service

I signed up with them on 9/5/2024 and was told the dealership where my car was and I would receive a call about installation. By 11/5 we had not received a call so I phoned again. Was told installation would be 08h00 on 13/5. Morning of 13/5 was phoned to say it would now be afternoon of 14/5. Phoned and complained. Then they changed the installation to 14h00 on 13/5 without calling me. Now taken delivery and the Tracker system does not work and someone can only look at it on 20/5. I was promised an apology letter from their management by supervisor Nozinhke, but still waiting days later. I feel they owe me a complete refund, as they have broken every promise made, including their so called "piece of mind".