The $104 charge most commonly relates to the annual renewal of a Flights membership, which is priced higher than the introductory or base rate some customers recall from sign-up.
Other possible reasons include:
You purchased add-ons (Elite or Bundle Deals upgrades) in addition to the base membership.
Your membership was renewed at a different price tier than when you originally signed up.
Multiple separate subscriptions were active on your account.
Log in to your account and check Plan and Billing to see a breakdown of your active plans. If something doesn’t look right, contact support, and we’ll clarify each charge.