title: SSL certificate is valid but browsers say invalid
body: <p>I am looking a solution for hours but can't find any. I am using letsencrypt ssl via certbot.</p>
  <p>My domain is <code>ektaz.com</code> when I check certificate on browser it says</p>
  <p><code>Expires: 8 November 2021 Monday 16:24:33 GMT+03:00</code></p>
  <p>When I check it from server side with <code>certbot certificates</code> I get result as</p>
  <p><code>Expiry Date: 2021-11-08 13:24:33+00:00 (VALID: 39 days)</code></p>
  <p>But all browsers says certificate is invalid I don't understand why.</p>
  <p>Also I have renewed this certificate many times using <code>certbot renew</code> I had no issue so far. I have cleared all cache and tried result is the same. I restarted apache many times. Even restarted server but nothing changed.</p>
  <p>Server OS : <code>Ubuntu 20.04 LTS</code></p>