Disgrace & an inconvenience

I went to apply for a cellphone contract at I store, Somerset West, in Cape Town. This is an iPhone 13 pro Max which I have been waiting for since December 2021,over 2 months. Telkom couldn't process my application because they said I owe them 57 cents. Which I fail to understand because my contract ended last year September and I have been on prepaid ever since. I only buy data on my Bank App. I don't buy minutes, I don't even understand how their airtime advance works. I have never used it. The contract which ended last year was disigned in such a ways that I could only use the provided data, I couldn't top up. How can I owe 57 cents of all amounts. I paid the amount at PEP. It couldn't update now. It will only update during working days