Pick n Pay store account closure

I had paid off the settlement balance on my pick n pay store account on the 9 November, I have called them many times this week to close the account and its still not done, I then received an email stating that my account will only be closed after the next billing cycle, I called the customer service centre and they advised that the next billing cycle is on the 1 December 2019. Why does it have to take so long in order for my account to be closed, why cant it be done now upon my request? I did close other accounts and it was done between two to three days, why do I have to wait until the 1st of December for my account to be closed??