Subdomains and certificate not working?

Question

cloudflare

Hello. Could you tell. Tied the site to cloudflare for a free tariff.
I registered domains

and now my.site.com does not enter the house, writes that it cannot find ip.

and the www.my.site.com

domain is visited. Although for some reason it says that the certificate is invalid, although I generated a wildcard certificate with a sertbot .

Maybe some settings need to be done. Thank you.