************** on customers online orders

Dis-chem is dicriminating clients I ordered huggies Gold online at the price on sale for R179 and on check out it was R179 for 2 pack I paid for the huggies Gold nappies and they cancelled my orders as they state there was a system error but why is this only affecting a few people? Other stores honoured orders but the one I chose in Castle Gate didnt due to getting instruction from head office? Your explanation of a "system error" does not suffice, especially when other clients have received their orders promptly which underscores the inconsistency in your service.