There is a task where we ask to send us your e-mail. This action is completely safe.
If you are not interested in the reward simply ignore the icon and the quest.
Please aknowledge, that you won't be able to complete a quest, if your Facebook account is linked to a phone number instead of an e-mail. It can be easily changed. In order to inform us of your e-mail and receive the reward, your Facebook account should use the e-mail as a primary contact in settings.
To add an e-mail, please follow the link https://www.facebook.com/settings (or find the settings button in the upper bar of Facebook profile page) and add an e-mail to the 'Contact' section,then confirm the e-mail as required. Then set the added e-mail as 'Primary' and save changes.
And now you can reload The Ghost Tales and receive your well-earned diamonds! Good job!