Disgusting and poor service

I requested to have my MTN cellphone contract moved to prepaid on the 1st of November 2015. The call center agent advised that it will take 5-7 working. I called on the 7th day to confirm if my contract had been moved to prepaid and I was told that the retentions department did not action my request as yet. It has been escalated twice and still nothing has been done. I wanted my contract to be cancelled before I receive new data and airtime and this was not done. After explaining to the consultant that I need my contract to be cancelled and I do not want to be charged or liable for further costs I was then sent airtime and data which I clearly stipulated that I do not want anymore. I called today again and I was advised it will take another 7 working days. I am deeply disappointed and disgusted with the poor service being a loyal customer to MTN for 8 years. I think it is time to move to another network and I will never advise anyone to use MTN again.