Woolworths worst experience

the worst business to deal with, it is now going on my 5th month of sending proof of payment after they send debt collectors for me, i have been making my payments every single month for more then the minimum and payments are made at least a week before the due date, yet for 5 months they cannot allocate to my account, then tell me i am in arrears, i am really very upset, GET YOUR BUSINESS IN ORDER WOOLWORTHS, they cannot even tell me how to cancel with them idiots