If you’ve kids in the house, you’ll probably end up in this situation someday. iPhone X has a security feature that if you enter the wrong passcode 10 times it locks your phone to save your data.
The only way to unlock the phone is via using iTunes. You surely have iTunes if you’re an iPhone user to keep your contacts, Photos, and Settings synced to your laptop or computer.
If you forgot your passcode, or if a message says that your device is disabled, follow these steps to remove your passcode.

Unlock disabled iPhone X via iTunes :

First of all, you need to shutdown your iPhone. For this, you have to do a force restart. To force shutdown, press the volume down key and side key on the iPhone X.

Next step is to connect iPhone X to the computer using Lightning cable.

Later boot iPhone in recovery mode. To do this Tap Volume Up and Volume Down key then Hold side key until you see the recovery mode screen.

Now download the software update or restore file from the iTunes. It will take time depending on your internet connection speed. Size of the restore file is around 2.77GB. Once the restore file is downloaded, click on the restore button in iTunes. It will reboot your iPhone to start the restore process.

You can also update the iPhone software but it will not unlock your iPhone. It is better to back up your iPhone occasionally to save the important data in such situation. You can use the latest backup to restore your iPhone.

When you see the option to Restore or Update, choose Restore.

Restore process will take around 15 min.

When the restore process is completed. Your iPhone will boot like a new one and you’ve to do the initial set up. Restore will also delete all data on your iPhone.

When you reach the Set-Up screen while restoring your iOS device, tap Restore from iTunes backup. Select your device in iTunes. Look at the date and size of each backup and pick the most relevant one.

Now, Your iPhone is unlocked and ready to use.