This wikiHow teaches you how to remove a Facebook Messenger account from an iPhone or iPad. The procedure does not allow you to permanently delete an account, it only allows you to log out from your mobile or tablet.
Steps
Step 1. Open Messenger on your iPhone or iPad
The icon looks like a blue and white speech bubble containing a lightning bolt symbol. It is located on the main screen.
Step 2. Tap your profile picture
It is located at the top right.
Step 3. Scroll down and tap Switch Account
The icon looks like a blue key. The list of associated accounts will appear.
Step 4. Tap ⁝ on the account you want to delete
Step 5. Tap Remove Account
A confirmation message will appear.
Step 6. Tap Remove
The account will then be deleted from the application.