Sudden Price Increases

In Sep 2020 I signed up on the Vuma R629 fibre package offered by Mweb. The first 3 months, billing was correct. Come January & February premiums were increased to R639 without notification. In March premium had now increased to R689, still without notification. When I called in this morning 28.04.2021 to inquire, I was informed the reason was because Vuma had upgraded or improved the services they are offering. Why is Mweb charging customers for these upgrades without consultation??? Is Mweb trying to say that every time Vuma upgrades their services, clients will have to pay extra all the time. This is a rip-off considering that most customers are bound to contracts and now paying different amounts to those they had originally signed up for. This is a disgusting move by Mweb, you don't respect your customers and the money we pay.