Paid up Letter

I had an account with Home choice which was handed over to Norman Bissett & Associates, also known as the Nimble Group as I struggled to pay due to unforeseen circumstances. I was called last year in November 2014 with an offer to settle the account with a discount. I managed to settle the account. I never received a paid up letter. I received a call almost a year after from HTN attorney saying that I still owe home choice, I called home choice they said I never settled the account. I managed to get the number of Norman Bissett, contacted them on their they told me that I settled the account and that they will request a letter which their admin will email to me. I am still waiting for the letter to give to HTN as proof that I have settled the account. I have contacted Norman Bissett and associates several times but I have still not received the letter. This was my last option to get my letter because it is on your records all your consultants that I have spoken to informed me that I have settle what is so difficult in just typing a letter and giving it to me. The above consultants I have spoken to, they promised to email the letter but nothing. still waiting for the letter