The gift card has not been added to the collection
The card distributed via e-mail "Feast of the Victorious Dead" was not added to the queue after pressing "claim".
[Deleted User] commented
The card was not added to your collection because you weren't given the card. What you were given was the Card Style.
Notice how Feast of the Victorious Dead in your search looks like the middle one in this attached pic rather than the one on the right?
For this issue, please submit at: https://mtgarena-support.wizards.com/hc/en-us/requests/new and select 'General Questions'.