My iPhone 4 phone number is disconnected and I can't use FaceTime or iMessage
Do you have an Apple ID? Also, just to confirm, what version of iOS are you using?

To use FaceTime with your Apple ID, navigate to Settings → FaceTime and tap Use your Apple ID for FaceTime.

To use iMessage with your Apple ID, navigate to Settings → Messages → Receive At and tap Use your Apple ID for iMessage.

Other Troubleshooting Steps:

Note: After each of the listed steps, be sure to try the steps listed above


Update to the latest version of iOS.
Ensure that you have an active Internet connection. You can complete activation using Wi-Fi or a cellular data connection. Check your Wi-Fi network using standard Wi-Fi network troubleshooting.
If you receive an error when signing in to your Apple ID, visit myinfo.apple.com, sign in to your account, and ensure that the primary email address has been verified.
Ensure that FaceTime has not been restricted: Settings → General → Restrictions → FaceTime.
In Settings → General → Date &amp; Time, ensure that Set Automatically is on. If Set Automatically is on, but the incorrect time zone is displayed, turn Set Automatically off and then choose the correct time zone, date, and time. Then turn Set Automatically on again.
Enable iMessage and FaceTime while connected to another Wi-Fi network in a different location.


You can check if Facetime / iMessage is activated with the following steps:


Settings → FaceTime → You can be reached by FaceTime at:
Settings → Messages → Send &amp; Receive → You can be reached by iMessage at:



If you look above, you can see an example picture. Yours will not have a phone number, but instead your Apple ID.


See more steps and information in Apple Support article TS4268: Troubleshooting FaceTime and iMessage activation.