Deregistered phone number from iPhone. Now what?

After switching cell carriers my iMessages no longer sync between my iPhone and iPad. My iPad will only receive messages through my email/Apple ID and iMessages on my phone are normal. Per someone's advice I deregistered my phone number on my iPhone hoping that a good reset would make it all sync again. Now my phone will not let me reregister my phone number and so I'm left with no iMessages on either my phone OR my tablet...please help.