First of all, this is NOT Samsung's fault. It only affects some AT&T phones. But if you're affected, you will want to make sure that you're safe!
http://mashable.com/2017/08/16/samsung-galaxy-note-4-recall-fire-risk/#YoCE.aBWCOqP
http://mashable.com/2017/08/16/samsung-galaxy-note-4-recall-fire-risk/#YoCE.aBWCOqP