Ticket options and other offers (e.g., parking, t-shirts, etc.) are determined by artists, teams, venues, and/or promoters. Ticketmaster does not control ticket options and other offers because we don't "own" the tickets and other inventory we sell - we're simply selling them for the artists, teams, venues, and promoters.
Often, things like discount ticket options are limited-time offers and it could be that time ran out while the tickets were in your cart. If another item such as parking or t-shirts is unavailable, they may have simply run out of space/stock.
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