Vodacom and Elite mobile is ******* and ***********

I went into Vodacom Menlyn to sort out a Data contract on 13 February 2020. They told me I must phone ***. I spkoe to a Miss Naidoo at 9:24, she told me I can do an Upgraded on my handset. I Told her I don't want to because it is to expensive, have been to Vodacom week before to find out. She told me she can give me the new Iphone 11 for minimal additional cost. She told me that she can give me better package with data and the new IPHONE 11 for only R11 additional cost on my total vodacom package. My Total package used to be R 2567.69 so addtional R 11 wil be R 2578.69. I Received my invoice en of February with Invoice amount of R 3216.56 . I phone vodacom an Elite mobile for two weeks now to listen to the recording on the agreed amount with absolute no success. No one has listen to our recording and they are also not allowed to mail me the recording. who can help me to reslove???