I am a completely ethical blogger, and have not purposely done anything wrong.
The robot.txt file is fine and google search console says, there is no crawl error or any issue with the site. It also has sitemaps.
The issues that might be:
The blog is mapped to blogger and earlier had http which is now https. I have canonicalized versions to https://www version.
I once had been given an offer by someone that he would get me quality backlinks through Fiverr. I am not sure whether that is the culprit. But I had stopped taking that service after a week. I think that if at all that would have harmed, it would be in other ways and would not show 'blocked by robots' error on search console.
[I also posted this in a discussion on robot. i think that stays there. the forum has asked me to post in the beginner's area since I am very new. So repeating. Hope this is ok.]
Posted screenshots here:1. robot.txt teser; 2. sitemap