Eneba Gift Card Deactivated

I purchased an Amazon.com gift card worth 1,000 USD today through the Eneba website. When I tried to redeem the code on my Amazon.com account, I received a message stating that the gift card has been deactivated and it could not be applied to my balance. Right after seeing this error, I contacted Eneba customer support and explained that the code is deactivated, but they have only kept me waiting and I have not received a clear solution or replacement so far. Considering the high amount involved, this situation is very stressful for me and I urgently need this issue to be resolved. I request that a valid and working Amazon.com gift card code for 1,000 USD be provided to me as soon as possible, or that the necessary action be taken so I can use the balance without any further delay.