Using iPhone as iPod, help with Facetime and iMessage

We passed my iPhone 5 down to my daughter when I got an iPhone 6. There is no phone number associated with it anymore and no cell service going to it, so it's basically being used as an iPod for music and pictures, etc. However, I'm having a hard time getting Facetime and iMessage to work. I signed her up with an Apple ID and her info has been verified by Apple and all that. But we've been stuck on "waiting for activation" for over a day now. I've tried doing a hard boot, tried resetting our Wifi info, tried toggling iMessage/Facetime off and on several times, etc. All the help topics I've searched for have been for iPhones with cell service activated. Does anybody have any advice?