Telkom should change to Helkom

Octiber 2019 i did change banks where my salary is paid in. I did contact Telkom to inform them about my new banking details for the debit order. I informed them i prefer to to eft payments and from that very month i started with my eft payments. My account is up to date. November 2019 they started to put debit orders through on different dates in one month. I don't keep a lot if money in my account because of the crime in the country, i always transfer money money as required into my account. End of April 2020 i received an account of R 920.55 (my installment us R 249-00 pm for a data contract). I contacted the billing department and they informed me that eveytime the put a debit order through and there is insufficient funds theycharge me R 202-00 extra, now i must pay the R 202-00 + the bank fees extra on an account that is paid up to date, and it is negative on my credit score.

I did try to resolve this with the accounts dept at Telkom, but the ability from their sude is as much as a Zero