Internal processes and departments do not communicate

I have requested cancellation of my service but it shows I will be billed for installation that happened in Nov 2020. Please note that the cancellation on Nov 2020 was due to an error on your internal systems. I had been assured that my initial cancellation would be reverted on my behalf and this was not done. This caused an interruption in my contract that started in Sept 2019 and that was held at the same address. You are once again attempting to make money off me due to you own mistake. I have had good experiences with WebAfrica, but I have also had the worst experiences.