Account not credited with payment made a month ago

I paid of my account in full on 15 January 2015. I received my account statement as per usual in Feb only to see the payment has not been credited. After many emails and calls nothing has been done to date to rectify this. I will be closing my account as this is just unacceptable and incredibly disappointing service from woolworths. The hassle to get this fixed is just not worth it.