Design Patent Stopping Us From Selling !?

My brother and I don’t know what to do. We have been selling this product for 18 months now, and recently we made our biggest order yet. The product has been doing really well for us recently. A design patent was raised against the listing and we are now no longer able to sell the product. We spoke with the partner of the person who raised the design patent, and he says it’s the action of his U.K. dealers. So I’m guessing he favours our competition over us as they might buy directly from him? We have offered to buy directly from him but he is satisfied with the current market volume.

We have 2,500 units stranded which cost us £6,150. What the f@*! do we do!?!?!?!?