Some companies "block" a certain amount of money on your card, so they can make a deduction against it later. For example automated gas pumps can "block" more t

Some companies "block" a certain amount of money on your card, so they can make a deduction against it later. For example automated gas pumps can "block" more then they probably charge, so the card can not be drained while gasoline is put into the tank. https://www.streetdirectory.com/travel_guide/164670/credit_cards/what_is_credit_card_blocking_and_how_to_avoid_it.html#:~:text=%22Blocking%22%20means%20that%20a%20hold,it%20from%20your%20account%20balance https://www.streetdirectory.com/travel_guide/164670/credit_c.... This might be a less notorius explanation then other which are offered here.