Free 3 Months Amazon Prime or $15 Amazon Gift Card for World and World Elite MasterCard Cardholders @ MasterCard

New-to Amazon Prime (including trial) customers will enjoy 3 months (90 day) membership. Existing Amazon Prime (non-trial) customers will receive a AUD15 Amazon gift card directly into your Amazon wallet.

The exact same as this deal but now non-CommBank Mastercard holders can try and their luck. I was able to successfully get a $15 Amazon gift card. Note that some Platinum cards are actually World Mastercards.
Update: If you don’t have an eligible card, follow this comment thread for an easy loophole method. Full credit to doweyy

Once you are successful, to get $15 Amazon credit click “Sign in” as shown here. It will only add a $15 gift card to your account if you already have an active paid for Prime membership on that account. Trial Prime membership won’t work – It will be replaced by 3 months membership.

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