Promotion on Bio Classic washing powder

We whent to Pick & Pay to purchase Bio Classic washing powder as it was on a special. At the shop there was no stock and I received a rain-cheque. Before the expiring date I phoned Pick & Pay customer care line explaining the situation, the lady returned my call after contacting Bedworthpark P & P. She assure me that the expiring date does not lapse and they will contact me when they receive stock. Now two months later nothing heard from P& P. It is hard to believe that they did not received stock.