I received the following error:
Your recent gift of < Steam Game > from < Steam Gifter > has been revoked due to a problem processing payment for this item.
The games associated with this gift can no longer be played as a result. If you would like to purchase this item, visit the Steam Store. Otherwise, you may choose to delete the local content associated with this gift.
This message indicates that a gift sent to your account has been revoked. The most common reasons this will occur are:
If you believe there has been an error, please contact the person who sent this gift.
The subscription to the gifted game is no longer valid. If you wish to continue playing the game without losing any game progress, you will need to purchase the game through Steam.
Never accept a gift from someone you do not know.
Additionally, do not pay someone to gift a game to you.