iMessage not working between 2 iPhones

My wife and I can't use iMessage between our phones since Thursday night. I've tried everything.

-- turned on airplane mode on both phones to reset wifi
-- turned off iMessage on both phones
-- signed out of iMessage through Apple IDs then signed in. We login with my same email account but only use our phones for iMessages
-- both phone iOS are updated
-- restart of phones

Any other tips? Driving me crazy. Thanks!