Overbilled Customer for Canceling my WI-FI of almost 4 years old.

To Whom it may concern

On 17 January 2020,i decided to cancel my WI-FI with Telkom. I contacted the contact Centre and i put in one moths notice to cancel as the contract is almost 4 years old. I specifically asked if there is a cancelation fee f which the operator answered "Only if i want to cancel it with immediate effect". She explained to me that i will only be charged for the month (15 January to 15 February).On Saturday 15 February 2020 they debited my account with an amount of R2400.I immediately called the contact center and is was told that the billing department will only be available on Monday after 08:00.In the meantime i reversed the debit order and this morning i called the Contact Centre (10213) and held on for 59 Minutes and hanged up. After about an hour i called them again, holding of for 1 Hour and about 13 minutes and than hanged up again. I really don't know what to do cause even at the Telkom store i was told that the contact center is the only once that can assist me with this issue.