No respect for their own contracts

I upgraded in 2023 and signed for a 24 month contract at R679 x 24 months. Now, not even a year later, I receive an email stating that its time for Vodacoms yearly increase. You keep me to a 24 month contract, yet you dont abide to your own contract, Vodacom! This sort of thing didnt happen before as a contract is binding, so why is this happening now??? Unacceptable!