Why do I receive messages on iPad but not iPhone
I recently purchased a new iPad and a few days later my iPhone will not receive messages but my iPad does
Check in messages that text message forwarding is turned off. If you sign out of i message on your iPad this will start working again. I think the continuity features as of iOS 8.1 onwards will handoff and forward messages to your iPad. But first turn iMessage off on your iPad and then test it with your phone. Heres an article that may be useful If you can't send or receive messages on your iPhone, iPad, or iPod touch - Apple Support