Markham ruining my credit record

November 2013 I paid off my Markham's account. I emailed them proof of payment and settlement letter, yet till this day on my credit record still shows that I owe them.<br> <br> After a long trail of sending them email and phoning their offices and being provided a long list reference numbers, still no joy of resolving my issue.<br> <br> Every single time when I call their offices, all the consultants require me resend my proof of payment.