is there anyway to know why and by what rules it got blocked and how to prevent it from happening? as i dont see it in the firewall events page(which until now I believed it would show all the requests who got the captcha page)
It’s actually there, but the Firewall Events UI is not very reliable, as often it will not return an error when for some reason it can’t retrieve records. All you get is a “no results” kind of return, which is obviously ambivalent.
Firewall Events does includes events from IP Access Rules
Somehow Cloudflare did not include Facebook crawler (nor Twitter’s, GTMetrix and other popular tools) in their list of known bots. So any blanket firewall rule such as blocking by country should be edited to exclude the AS number of these crawlers if you make use of them, as well as of course the known bots list.