It seems that the page you requested returned a 404 error. Google discovered this URL without any explicit request or sitemap. The URL may have been found as a link from another page or may have existed before and was subsequently deleted. While 404 responses are not necessarily problematic, it's advisable to implement a 301 redirect if the page has been moved to a new location. This helps in maintaining a seamless user experience and informs search engines about the updated URL.