Mtn contract cancelation

Contract expired on 6/01/2024.You have to call them after the date to cancel the contract, but then you are informed that the end off the month they will deduct another payment you will get your data and minutes again. But then on the 6/02/2024 your contract will be canceled and you loose the minutes and date .Why does a contract expire on a date but can only be canceled a month later 😡