Wonga Loan

I had a loan with these people and I paid the loan and one day I asked on an email what do I still owe on the loan and I got the reply that I don't owe them any money. I then asked for a letter to state that I don't owe them anything then they came with the story that I still owe them money and that I must contact the lawyers. I contacted them and they told me I still owe them money. I then spoke to the lawyers and told them that I have proof from Wonga's side I don't owe them anything. The person at the lawyers office asked me to forward me the email, so I forwarded the mail and he told me that he will contact me back the same day still. I have not heard back from him till today and they also ignore my emails.