Open Messenger
Open the chat with the person you want to remove
Tap the person’s name or the info icon at the top
Scroll to Privacy and support or People in chat
Select Block or Remove from chat if available
Confirm the action
If it is a group chat, open the group info
Tap the person’s name
Choose Remove from group
Confirm the removal
If you want to stop future contact, block the person in Messenger or Facebook