Cooling off period

Yesterday MTN phoned me to upgrade my contract for the phone ********** 890. I n the call I agreed to upgrade and selected a R399.00 contract with 500 minutes air time. In the phone call it was repeatedly stated that I had a 14 day cooling off period. Later in the day my daughter who actually uses the phone that I was upgrading told me that she does not need 500 minutes, she only needs 200 minutes. I thus phoned MTN at the call centre number given in their email. After waiting a long time the call centre operator eventually came on the line & said she could not help that I should actually go back to their sales department. She then promised to put me through, instead after a long wait the phone went dead. I then called back later in the day & again was told they could not help but they would forward my query. I then called a 3rd time and my call was put through to sales who then said I would need to wait 90 days to change to the lower package. When I explained to the operator that there is a 14 day cooling off period, she put me through to her supervisor who said she could not help but would forward my query to another area. I then started explaining to her that they would need to phone me on an alternate number to the number than the phone number which I was querying, again the call was disconnected. My point is that I do not expect to be given the wrong enquiry number on a letter sent to me,wait forever, have the phone put down on me several times & I do expect the operators to know about 14 day cooling off clause in the contract.