Hey Jaychris2235,
We'd recommend looking through the tips here, in order: If you can’t turn on or sign in to iMessage or FaceTime - Apple Support
If you receive the same error, contact Apple Support for additional assistance from there: Apple Support
If you are able to sign in, but it says "activation pending" or some other message, it may take up to 24 hrs to activate. Should the service still not be activated at that point, then contact Apple Support for assistance.
Take care.