Refusal to issue paid up letter

I too out a loan on the 10th March 2015 and refunded it on the 17th March 2015 because I no longer required the money.<br> I called to request a paid up letter and they are telling me I need to pay interests and all and then they will generate a settlement amount for me.<br> <br> I spoke to a lady on the 17th March informing her of what I want to do and we counted 5 working days and she informed me that yesterday was the last day I could make payment. That is exactly what I did.<br> <br> <br> The customer services today are refusing to give me a paid up letter.<br> Please assist urgently. Proof of payment is attached and they do acknowledge receipt of payment on the 17 March 2015.<br>