@IT-Works, you've had Let's Encrypt certs since December 2016, but your most recent one was issued in January of this year. Whatever process was supposed to renew the cert, didn't. But we have no way of knowing what that was if you don't tell us.
Sorry, my choice of words wasn't specific enough. What I meant was the added value of --force-renewal if the renew command doesn't work? certbot renew should work or at least try to renew. If it tries to renew and it doesn't work, forcing it to renew doesn't have any added value.