Unable to redeem Clubcard points.

I accrued in excess of 1,100 points on my clubcard and despite several efforts I have been unable to redeem any points. Every time they tell me the card is not registered. On two occasions the store ( Cobble Walk) put me through to Customer service and they ensured me the card has been registered and issue has been resolved. This morning my card suddenly reflects 0 points whilst I have been unable to redeem anything thus far! For a multinational company this is really shocking. If you wish to run a loyalty program this way, you might as well not have it.