Incorrect listing on credit beraus

Nimble Group have listed missed payments on my account bought frm African bank. The only thing that makes angry is that I have never missed any payments with them they were debiting their money every 15th day in my bank account. I have finished paying in March but missed payments are still in my credit profile. I tried to apply for a bond but those missed payments are preventing banks to even consider my application. I don't even know why did they list missed payments in my account as I was even paying more than the agreed installment.