DATA removed without consent

Good morning. When I upgraded my contract last week Thursday, I had 732 MB of data. Instantly it was depleted and I advised the lady who upgarded me at the MTN store of this and she told me the phone is still rebooting but it will correct itself after some time, and if not I should call the call centre. On Friday my data was still not reflecting so i called the call centre and I spoke to Mr. Y Ford who assured me that this is an error and that it will be fixed and refunded back into my account by latest Monday. I called the call centre this morning and spoke to a Ms. N Solomons and she stated that feedback has been received and the data will not be refunded if I upgraded. I am not impressed with the outcome and the lack of feedback. No one came back to me, I had to call MTN for feedback. Secondly, I paid for the data, mtn does not have the right to take it away without prior consent especially because I asked the relevant questions. I should have been given the information for me to make an informed decision. I will proceed to send an email to the CEO. I work in a service industry and this is not what I expect for a service I paying for.