I got kicked out from the event even though I gave a gift!
That is not a bug or issue, you most likely forgot to submit your gift. Remember that after depositing the items you had to select them as your gift and submit it through the Secret Santa event page.
Trade Offer
Auto-Sell Hats
Automatically sell up to 100 of your eligible hats at once.
Don't worry: we won't take special items, including painted, low craft numbers, special levels, spells, killstreaks, etc.
Autosell Cards
Automatically sell up to 1,000 of your eligible cards at once.