Check out the guide properly and know about how to deactivate Facebook on app properly. For this, click on upside down triangle in the top right corner of Facebook page. Now, proceed to settings and choose your Facebook information in the left menu. Here, tap to deactivation and deletion. After that, choose to deactivate your account and then click to continue for account deactivation by following the instructions to confirm. To smoothly reactivate your account, you can log into account online or use Facebook account to log into third party application.