How do I remove myself from ITC when I have paid Avon

AVON The service is bad, how can I get assistance I paid my balance I was owing Avon in 2017, and till TO DATE I'm still blacklisted, I sent proof of payment, they keep on telling me the reference is wrong and I explained to them, that my cellphone number is on the receipt,, they are expecting me to pay another money, I sent few emails, and everytime I have to explain my story to a difference person.