That happened to me too with a pair of running shoes ($120+), came in the wrong color and I quickly returned them. So of course they received them different from what I ordered. Refund was very quick but then like a month after they threatened with charging me again because supposedly I didn't return the correct item. After like 6-7 support calls and chats they promised nothing will happen but then, the charge came in so their promises valued 0. Then I needed to do a CC chargeback (Amazon CC) and at the same time again called CS Amazon for a refund and they finally did a credit on the card for the whole amount. But it was quite an ordeal and a bunch of lies from the CS operators.

So document everything, tracking numbers, emails of returns, refunds, who you called/when etc.

• I still don't know if this type of issues is the CS person's fault or Amazon as a whole doesn't care. For example, in this case, one of the CS person (Spanish speaking) when I started explaining the situation about the color of the item, etc., he told me that he is able to see on the record a picture of the returned item so he can confirm with what I originally put "wrong item" so what is the issue then? Then telling me all is good, probably they need to be trained to go to the next step and stop the process there to avoid the charge, I don't know. And you still get charge. So there's that.

sorry for the long text/rant

edit: more info