Can Ctrip customer service ask the hotel to provide the guest ID card?

Of course. In order to confirm the guest's identity and reservation information, Ctrip customer service will share the necessary information of the guest with the hotel, including but not limited to name, contact information, ID number, etc. This is mainly to ensure the accuracy of booking and provide better service. Therefore, Ctrip customer service can ask the hotel to provide the guest ID card.