“Start new conversations from”

Hello and welcome to Apple Support Communities, Happy5556,

We understand you're trying to change where new conversations are started from on your iPhone. We'd be happy to provide information to help you out.

Check to see if turning off and turning back on iMessage helps:

If you can’t turn on or sign in to iMessage or FaceTime - Apple Support

Turn off and restart iMessage and FaceTime

1. Go to Settings > Messages and turn off iMessage.

2. Go to Settings > FaceTime and turn off FaceTime.

3. Restart your device:

iPhone

iPad

iPod touch

4. Turn iMessage and FaceTime back on.

Regards.