a warning is a warning, nothing more, the website is working without any problem. The problem is that this information is visible on your website, this is a very sensitive information. A hacker can provoke such messages and hack your website. On a public website these messages should always be hidden. Please check your hosting panel -> PHP settings and search for “Show Error and Warnings”, and turn this option of. Please let me know if you don’t have this option in your settings, then there is another solution.