Connect new iPhone to iPad Facetime

I just got a new iPhone. When trying to make a FaceTime call from my iPad, I get an error message: iPhone calls not available. Your iPhone must be signed wit the same apple id for FaceTime and iCloud to make phone calls from this iPad. I checked settings and the user ids and phone numbers match. I can't figure out how to resign into FaceTime - I can't find the option. I've also turned on 'connect to other devices' and listed the iPad.