You can't log on to your Chromebook? Your password isn't working and you are sure you have the correct password, try removing your account from the device. This is entirely safe. This will not deleting your Google account. All of your files that are stored on your Google account will remain. This will only delete the account from this particular Chromebook.
On the login screen, click the down arrow by your name and choose ‘Remove account’.
Click ‘Remove account’ a second time.
3. Click ‘Shut Down’ in the lower left corner.
4. Click ‘Shut Down’ a second time if necessary.
5. Wait 30 seconds until you try to log-in again.