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Yesterday I bought a heating pad at Walgreens and used my HSA debit card. It was a HSA Over-the-counter Eligible Expense. However, after the purchase I realized it wasn't what I actually needed. So I took the heating pad back to Walgreens to return it and the cashier gave me cash in the amount of my purchase.
Now I don't know what I need to do since I essentially just received around $40 dollars tax free. Do I report it on my taxes, send it back in to my HSA account, pocket it and act like it never happened? Any advice is greatly appreciated!