Lack of follow-up or explanations for Woolworths problem

Very unsatisfactory service from Woolworths Customer Care. My account card suddenly gets "blocked" for no reason. Credit record is good and payments up-to-date. Store manager says to call Customer Services. Customer Services says to go to store and have someone there call them to get the card unblocked. It's all too much trouble for the customer because of a problem in the Woolworths system. This has happened to me before - again, for no apparent reason - and no-one ever follows up to explain why it's happening. Just logged complaint ********** 5 at 10h26 on April 2nd.