If you are too busy to chat with your friends or simply don’t want to be bombarded with messages when you go online on your mobile, this guide will teach you how to change your online status on Facebook Messenger to appear offline.
There, you will see the Show when you’re active option. To appear offline, you need to turn deactivate this setting. To confirm your changes, select Turn off in the dialog box that appears
N.B. After deactivating your online status, you won’t be able to see when your contacts are active or have been recently active on Facebook Messenger.