Sorry this is a daft question but I can’t find answer on google. I have two items to return to Amazon (both in their own cellophane packing which havent been opened) but I’ve lost the Amazon postage bag. The post office will print off the returns label from the barcode but will the big green Dunelm bag with Dunelm written across it confuse things and end up with it at some Dunelm returns warehouse? Do I need to not be tight and buy a plain postage bag? Thanks.