Okay, Sritharan Great! Le me explain you why crawl errors happening, There are two main reasons to happening to the crawl errors,
Site errors: Site errors are including all the crawl errors that are related to your entire site. if you are getting any site errors on your Google search console, you need to know what kind of site errors you are getting.
– DNS Errors
– Server errors
– Robots failure
URL errors: Googlebot is unable to access a specific URL not your overall site.
– Like 404 errors
You can find out the Crawl errors status on new Google Search Console, these errors are reported on a URL-by-URL basis in the Index Coverage section.