My text bubbles are now green. The iMessage won’t activate. Why?

If it took a while until your iMessage could be activated, it may take as long for the activation of FaceTime.

Are you trying to use Wi-Fi or mobile Data to connect to FaceTime?

Use FaceTime with your iPhone, iPad, or iPod touch - Apple Support

Did you already try the troubleshooting, mentioned in this article?

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

You‘re welcome 🙂