We can remove iCloud Lock from clean devices that someone has forgotten the password for, yes. But, we absolutely cannot remove iCloud Lock from a device in Lost Mode.
To check if your device is in Lost Mode, go to the "Activate" screen which asks for your iCloud credentials, and look for any of these. If any are present, then the device is in Lost Mode, and we cannot help with it:
- "This device has been lost and erased"
- "Message From Owner"