How do I offer combine postage for multiple purchases bought at the same time, I have set up a postage rule but customers are still be charged the rates ebay sets.  All multiple orders can fit in one box, I had a customer buy 6 items recently, the postage is set at 2nd class tracked small box.  The customer was charged £9 postage, I was given 1 postage label so the items went together in one box.  This can't be right.