google search console issue your sitemap appears to be an html page. please use a supported sitemap format instead.

 Hi Everyone 
you can use below sitemap for your website to solve your sitemap appears to be an html page. please use a supported sitemap format instead issue in blogger.
to solve this issue, go to setting of your blogger. 
enable custom robots.txt
an enter below text in custom robots.txt box and save it.

User-agent: *
Disallow: /search
Allow: /
Sitemap: https: <your website URL>

If you still face any issue please write your issue in comment section.