facetime and imessage problem

You need to change/add the number on your Apple ID. After the change, allow up to 24 hours for the change to sync. Before trying to make the change, sign out of Messages/FaceTime on all devices/computers.

Apple ID - Manage  

In Preferences/Settings in both apps is your phone number checked?

ASC - Late 2012 Mac mini, macOS 10.14.6; Watch, series 5 GPS/cellular, watchOS 6.2; iPad Air 2, ipadOS 13.5.1; iPhone 8+, iOS 13.5.1; TV 4th Gen, tvOS 13.4.6;  HomePods, audioOS 13.4.6 and Airport Express w/ Airplay 2