My iMessage says inactive

My iMessage on my MacBook Pro receives text and iMessages but when I attempt to send one I get a message saying my "iMessage is not logged in" and it tells me to sign in. I click the sign in button and it shows me signed in already. However, in the left side of the box it shows my Apple ID and next to iMessage it says inactive. I can't click on this tab to see why. I have logged out and back in. I had a verification code when I first set up the iMessage app on my MacBook. I have checked all the settings any help link suggests, on both my phone and my MacBook; nothing looks out of line. Can anyone lend a suggestion, please?