Entering your passcode on the iPhone directly, turns off Lost Mode:
Turn off Lost Mode on an iPhone, iPad, iPod touch, or Apple Watch
When you find your lost device, do either of the following to turn off Lost Mode:
- Enter your passcode on the device.
- In Find My iPhone on iCloud.com, tap the device that’s in Lost Mode in the Devices list. Tap Lost Mode, tap Turn Off Lost Mode, then tap Stop Lost Mode.
Note: If you had any cards suspended when you put your device in Lost Mode (credit or debit cards for Apple Pay, or student ID cards or Express Transit cards), when you turn off Lost Mode and sign back in to iCloud, you can use them again.