Poor customer service

I have received an email from Vodacom on the 13th of August 2024 stating that I owe an exceeding amount from the initial contact agreement amount. I am confused as to how a R599,00 debit order for the month of July 2024 has become R1251,33. I have started my Vodacom contract last month and agreed to pay R599 at the end of the month, only to receive an email that I owe more money. Vodacom is trying to rip me off by charging me ridiculous amounts that I am not aware of. Vodacom fibre is ********* as they fail to adhere and provide honest customer service. Calling the customer service is helpless because you end up being put on hold for long hours without receiving any assistance