What does it mean when you go to a message and the FaceTime icon in the top right corner is outlined green? What does that mean?
Okay. Try and restart the phone to see if the icon persists. Most of the times this will solve the issue
Facetime is available to android and windows users.
Join a FaceTime call from an Android or Windows device – Apple Support (UK)
Maybe they have joined you in the past or they are on a facetime call right now.
Are you on an active FaceTime call?
Okay. Because when I went to my other messages of all the people who have iPhones theirs don’t do that. But, I’ll try that.
iMessage FaceTime icon outlined green
