Hello, help me translate this sentence, thank you. Please swipe your card when entering the door. If there is no card, please call the front desk.

Insert card to enter; If you don't have a card, please go to the front desk.

Generally speaking, for English public signs, you only need to say "insert the card to enter" and pay attention to the case. In fact, "calling the switchboard without a card" is an extended translation.

Swiping a card is generally used to swipe a bank card, which is a different action.