Why the letsencrypt certficate validity ended before the expiry date

I configured the letsencrypt certificate for my website which is hosted on centos 7 with httpd web server

On 12-07-22 I renewed the SSL certificate manually by using /usr/bin/certbot renew. Then checked the SSL validity on the SSL checker website. All is working fine and SSL validity shows as 89 days.

But when I check the SSL validity on 05-08-22 it shows only 2 days left. I don't know why the validity was reduced like this.

Then checked the certificate modification date and it still remains at the date 5-5-22 which is the previous certificate renewal of failed autorenewal attempt (i didn't check it while I renewed the SSL on 12-07-22).

Then manually executed the renew command again and checked all aspects. Now the certificate is working fine.

I want to know why the auto renew command executed perfectly and shows the validity as 89 days when I attempt to renew the certificate on 12-07-22. And why is it reduced when I check the certificate on 05-08-22 while there are 2 months left for validity?

webconfig file

<VirtualHost *:80>
  ServerName site.com
RewriteEngine on
RewriteCond %{SERVER_NAME} =site.com
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,NE,R=permanent]
</VirtualHost>
<VirtualHost *:443>
  ServerAdmin root@localhost
  ServerName site.com
   DocumentRoot /var/www/sitename
   DirectoryIndex index.html
   <Directory "/var/www/sitename">
        AllowOverride All
       Options -Indexes +FollowSymLinks
   </Directory>
   ErrorLog /var/log/httpd/error.log

   SSLEngine on
        SSLCertificateFile /etc/letsencrypt/live/site.com/cert.pem
        SSLCertificateKeyFile /etc/letsencrypt/live/site.com/privkey.pem
        Include /etc/letsencrypt/options-ssl-apache.conf
        SSLCertificateChainFile /etc/letsencrypt/live/site.com/chain.pem
</VirtualHost>

Now I setup the cron to run to check the validity and renew the certificate for every 2 month

Can anyone please give me an idea of how this was happening?