Unfair intentional charges by Payflex

They failed to debit my account on 15 September 2025 according to our arrangement/agreement. My account had money and I even went to my bank i.e. Capitec to ask why payflex debit orders didn't go through. They said my account doesn't have any problems (and there are available funds) because my account number is correctly linked to payflex. All my debit returned unpaid and got notifications via SMSs. They then send me several sms's saying they have added R125 because i didn't pay, and they will add another R375 if not paid within 7 days. I have tried several times to contact them using contacts appearing on their website using the below channels but they are not responding to my complains. i used these channels but all no response: Shopper Support Email: *** Phone: *** WhatsApp: +***0