I’m sorry to hear about your lost device. Since your devices are all connected via the same Apple ID and iCloud account, it’s difficult to selectively hide a shared album from just one of the devices.
However, you can take steps to secure all the data on your lost device, including your shared albums:
1. Use Find My iPhone: If you have Find My iPhone set up on the lost device, you can use it to put your device in Lost Mode or erase it remotely. Lost Mode will lock your device with a passcode and display a custom message with a phone number for you to be reached at. If you choose to erase your device, all of your information (including credit, debit, or prepaid cards for Apple Pay) will be deleted from the device, and you won’t be able to find it using Find My iPhone. After you erase a device, you can’t track it.
2. Change your Apple ID password: This will prevent anyone else from accessing your iCloud data or using other services (like iMessage or iTunes) from your lost device.
Remember, it’s crucial to report your lost or stolen device to local law enforcement. Law enforcement might request the serial number of your device, which you can find on the original box or receipt, or on your Apple ID account page.
Also, note that these actions may not be reversible, so consider the implications before proceeding, especially with the erase option. It’s a good idea to contact Apple Support directly for additional assistance.