Amazon review: Refund not credited to Prime Visa but added to "gift card" amount

I purchased an ice machine for $236.49 on Amazon and it was debited to my Amazon Prime Visa. The item did not work right so I returned it 3 days ago. The refund by default went as credit to my gift card amount and was not credited to my Chase Prime Visa. I called Amazon and they said I did not select my credit to go to my Visa and by default it went as a credit on my gift card amount. They said they did not now have the option to credit my credit card. It is fraudulent for Amazon hold my funds now that can only be used towards Amazon purchases and I have to pay the amount to Prime Visa account.