The new iPhone was released on September 25.
In a thread on Apples Support Communities, several users describe a similar problem.
Owners vented their frustration by voicing their displeasure on Twitter.
Nothing else is hot, not even the charging port, just the home button is on fire.
I have had the phone unplugged for an hour and the button is still on fire.
touch ID is extremely hot.
The hardware is replaced or repaired only when necessary.
source: www.techworm.net