I ordered and paid for one bag but was sent two identical bags in separate packages by the seller.
I contacted the seller immediately to inform them of their error. Their response was to send a reply a day later asking me if I wanted to buy the second bag at a discount. I replied and said no thanks as I have no need for two identical bags. They replied the next day again offering a discount and saying that maybe I could give it as a gift to someone or sell it on, and also that it was now no use to them to sell to someone else as they do not sell returns. I replied to say no thanks. Their reply, the next day, was to say that I should return it to them with a list of information including ebay id, my email address, my address, reason for return, etc, and a photo of my postage receipt and they will then refund my postage when they receive it back. Reading feedback on ebay for the seller, there appear to have been a few incidences where they've not been great with refunds so I was wary of paying the postage/being refunded for it. I have therefore replied that I will check the cost and then please can they send me the postage money before I return it.
Have I acted reasonably? Basically, I don't want to end up out of pocket due to someone else's error, I am fed up with the hassle that this is causing me, and although I am willing to do it, going to the post office to return the item will be out of my way and is difficult with two young children!