Hey Siri Not Working But Siri Can Hear Me If Home Button Held Down Iphone 7

Chosen Solution

As title says. Setting up Hey Siri does not work. But if I simply hold down the home button and talk to Siri it can hear me fine. Am I right in saying Siri listens through the earpiece mic for both of these?

Maybe the repair guide below can give you a hint. How to Fix iPhone 7 Hey Siri Not Working