Poor communication and unauthorised debit orders

I have been debited twice for my mobile contract this month. The second debit order was double my monthly invoice amount which essentially means I paid 3x my monthly invoice for May 2024. There was no prior communication that the amount was going to be debited nor any reason as my account is fully paid up via a monthly debit order. I’ve tried multiple times to contact Telkom directly including asking for an agent to call me back but I have not be contacted. If you phone their call centre you get redirected to their WhatsApp help centre which cannot be used on WA Business which means I’m unable to use this route to contact them as I have a business account.