ANSWER:

If they give such an option, this is permissible though it is not ethical for a Muslim to return it and make people lose money for no valid reason. He wouldn’t want people to do this to him. 

QUESTION: (I have searched everywhere, I don’t think this question has been asked), Amazon’s policy allows buyers to return items for a refund, even if there are no defects, solely based on a change of mind or personal preference (for example, not liking the item despite it working perfectly). Is this policy islamically valid? And will the refund I receive be halal for me?