I have walked through all the trouble shooting steps to send an imessage but it STILL does not work on my iphone.

I have walked through all the trouble shooting steps to send an imessage but it STILL does not work on my iphone. I have disabled SMS and MMS and imessage and restarted my phone and then enabled SMS, MMS and imessage and my phone still gives me a message to enable imessage. I have unchecked my phone number and my email address and restarted my phone and rechecked my phone number and email as well as signed in with my Apple ID and I STILL cannot send a message through imessage. Why is this so hard to fix?!