iMessage not working on Macbook Pro

My Macbook pro will not send iMessages. When i go to send a message it automatically says "Not Delivered". My Mac is up to date with all updates, i've restarted my mac, i've force quit messages app, i've signed in and out of iMessage on the mac, i made sure the iMessage accounts where the same, and i made sure i have send and receive on my mac and iPhone. Im not sure what else to do, my iMessage works fine on my iPhone.