Increase in monthly payment after end of contract.

My husband upgraded his cellphone contract at the same time as I did. He received an LG device as well as a VodPhone tablet. His payment was R1749.00 (estimate) a month. After the 2 years were up my contract went down but his increased by R100. Upon calling Vodacom customer care he was told it was the last month at that price. This occurred monthly. Every time he contacted them they said next month it will be cheaper. This month again it is R1800.00 and something. Upon phoning them again to query this he was told that he was given a special discounted price during the 2 year contract and therefore when the contract ended the price increased. I have never heard of such *******. In the 2 years you are paying off your device so how can it cost more once you have paid up the device. I honestly think I will try a different service provider now. Been with Vodacom for years but this is just insane.