That’s quite unfortunate and lame- I’ve noticed a lot of retailers will let you return online merchandise in the store but not store items to the site for situations just like yours. To make it more complicated some stores which let you return online items in-store have SOME ‘special’ items that have to be returned to online. Too much!

You could try calling the store itself and asking if you can send it for a refund/exchange. It’s a long shot because obviously if the manager you speak to agrees they can’t guarantee they’ll be there to receive it, so it is a liability for them.