Complaint Review: Walmart

Ordered a fitbit 5 , did not have sensor I wanted. I bought a fitbit sence insted. Anyways. I called and asked to return to store they said we will sent return label, ok so fedx picked up. Note I received the small watch in a huge box, and since they sent a return label I found a small box thinking to help there return shipping cost.

So now they refuse to refund my $146.84 due to the box they received weighing less than the box they sent me.. WHAT???? Walmart has stolen from me cause they also have the item.