Received paid up doc from NBA but Avon says I owe

I paid the account in 2013 and received a paid up letter dated 05/08/2013 and now I am getting different stories from the collections dep. one said the account needs to be removed from collections while another said I am owing Avon still. How come your website allowed me to place an order and did not indicate that I am owing. How come i am only hearing of this 2 years later now that I wanted to rejoin Avon. This is unacceptable. I am supposed to have received the correct info. from your creditors . How come I was able to get a paid up letter when there's a claim that I owe Avon now.Today I got an sms stating that I owe R572.75 order ref F3BG0061 AND ON THE PHONE i WAS TOLD i OWE R300. I have made countless calls to Avon to ensure that the account was up to date but back then such issues did not come up. Its expensive to keep calling Avon and have such things not resolved months later. Please fix this mess Avon.