Accidentally Marked an iMessage as "Junk"

Saw this question in here and I am not able to reply to it.

How to undo marking a message as "junk":

• tap 'edit' on top left of message app
• tap 'show recently deleted'
• tap the thread you want to recover and tap 'recover all'
• re-add the contact to your contacts list (in my experience, it deleted the contact when I marked it as junk)