'Non existing' Customer care from Mr. Price!

I've opened my account about a year ago. I've just paid my account in full, yet they did not receive my payment, and claim my account is overdue!! When sending WhatsApp as requested they waste your time as you have to fall into 'their' schedule. They tell you to contact the customer care number, but then say that no calls will be answered! How do you do business?? Can someone please update me and advise what they did with my payment???