Lidl complaint: coupons not working

I had managed to obtain a £10 lidl coupon plus coupon which failed to activate in the store, this was after several attempts, my lidl plus card activating and the intervention of the store manager who could not resolve the issue.

Also several other coupons failed to activate including 20% off harvest basket products 3 x packs of sweet potato fries at £1.49 each and 15% off of W5 products of which I purchased around £15 worth of products.

Whilst the savings are only around £12, this is a significant sum to me, I was shopping with my child and there was a degree of embarrassment caused to me at the till as the queue built up whilst the cashier and manager tried to sort this problem out.

I was luckily able to still afford to complete my purchases but had I been relying on the coupons to afford this it would have been utterly devastating to have to refund items to be able to complete my purchase.