Refund not paid out 4 months later

In April 2015 I over paid my account by R6000. I sent in a request to have the excess paid back into my bank account. Despite numerous email and phone calls I am yet to receive my refund. Woolworths appear to be very quick to take money from customers but not to pay back want is due. This have left a very bitter experience and view of Woolworths. I am a domestic worker and am struggling without these funds and yet Woolworths do not seem to care. Customer experience ZERO. Will they on me interest for the money I've lost - I doubt it. But they are very quick to charge overdue accounts.