Sizing Difficult

I ordered two of these in different colors and had to return both. I agree w/ other comments re: sizing - One does not order whatever might be your regular size. It's good that shipping is free because of the questionable fitting. However, I can see how this bra would be comfortable once a gal has correct size. I am thinking of reordering to try different size. But in the meantime, they've lost a sale. When trying to exchange for different size, it was indicated that these HAD to be returned for REFUND ONLY, not exchange. I don't understand that reasoning since the company has lost out on an order. Seems to me they'd want to keep customer(s) by allowing exchange. That's the first time I've ever encountered the total return practice within a business.