Poor service

Three months ago, I bought a data product from one of the sales consultants who called me from Blue Liquid Telecom (a Subsidiary of MTN). They did not need to deliver a SIM card as I requested that they load it to my existing account. I waited an entire month and they did not load the data but I was billed for this under my contract at the end of the month. So I decided to call them and ask them what was happening, they told me they didn't know what happened so I would have to investigate what happened, request a cancellation and reapply for the product. I told them I was fine and did not want the product anymore so they could cancel and refund me. After another month, they did not come back to me with a resolution or refund me; instead, I had to call them. They told me that the issue was investigated, the product was cancelled and I will be refunded into my account in 7 to 21 days. It is currently the 29th day and I have not been credited with my refund or received a communication about what's happening. Instead, I have to use my one airtime to call them and ask them. The service from this entire experience has been poor. I am not happy because I can assure you that If I owed MTN for three months, they would have charged me interest, they would have sent me multiple emails, called me to request for their month, and reflected this on my credit record.