MTN contract increase of 01 April 2023 not part of Initial agreement.

Upgraded and took a new contract for 2 years for a set amount monthly. Now received an e-mail that the contract is going up as of 01 April 2023. The terms to increase the contract are not on the initial contract. Complained to MTN and ICASA. No response. The amount given on the contract is not the true amount. Call it bad advertising.