Vodacom is changing my signed monthly invoice amounts without any notice or reason

My Review on the 2nd of August 2017: I upgraded three phone contracts in April/May 2017 with the iphone 6 special. One line on the R399/Month Smart M top up + and the other two lines on the R349/Month Smart S Top Up +. After the first month I decided to change the other two lines from The Smart S Top Up + (R349) to the Smart Top Up M + (R399/Month) I contacted the vodacom customer care with my querie and they said on a recording that they will be able to charge me the same R399/Month amount on all three contracts, exactly the sames as if I upgraded them from a vodashop. Then my billing came and vodacom charged me the wrong amounts on my two lines. I have spoken to Olga Dorosamy and Katlego Senosi from their Solutions Department with empty promises. I have not received a call back from any of them yet as they promised me. I have also spoken to Tumi from the 24h sms follow-up department with no help at all. Every time I contact the 082 111 number they always tell me that the person I am looking for is not working in the region my phone call came through and I have to try my luck again by calling the number again. I cannot believe such an established company gives such poor customer service. I am now waiting for Zweli Ngwenya to contact me. Always rememer to get the contact person's surname and area where they work when you want to follow up on your problem. After I send my review on HelloPeter, I have been contacted by Rudi-Jo Stephan Le Roux. He told me my billing issues would be resolved and I would also get a R300 credit on my bill. I do have a sms from him as proof of my billing and credit. This morning I saw that my billing was still/again wrong and I haven't received the promised R300 credit from the mistake vodacom made on my billing.!

I received an e-mail from ********** regarding my credit. Everything was 100% up until December 2017 when all of a sudden my agreed special iphone 6 contracts went to their original price??????? I have been struggling with over 9 reference numbers and all come back saying I have done a migration or my discount is now over without me doing anything to my contracts??????

Some of my Reference numbers are: 1- ********** ********** , 1- ********** ********** , 1- ********** **********

All of a sudden their are no recordings of my migration arrangement over the phone back in May/August 2017. I requested my original contracts of my three numbers and received unsigned documents with wrong figures. It shows on one of my numbers I should pay R70.00 for an iphone 6 and R70.00 Smart S+ package on the unsigned contract.

How can I pay an installment for three lines from August to November and then all of a sudden Vodacom without any notice change my figures to the original prices? Now I have to waste my time and money on another error.