Airpods aren't default output for phone calls
If I am using my Airpods just to listen to music and then someone calls me, when I answer, it thinks I want to use my built in iPhone microphone/speaker as if I wasn't using Airpods. Every time I answer the phone, I have to change the audio setting from 'iPhone' to 'Airpods'. How do I get my Airpods to be the default option for phone calls?