Https does not work on subdomain

[mmaismma]

I have a website outre.ml. I got an SSL certificate for domain outre.ml from InfinityFree’s website. I created a subdomain assets1.outre.ml. Now when I try visiting https://assets1.outre.ml/. It returns ERR_SSL_PROTOCOL_ERROR. I tried getting an SSL certificate for the subdomain but when I go to edit the CNAME record it does not give an option for assets1.outre.ml in the domain section.

[Admin]

If you can add CNAME records for outre.ml, you can also add CNAME records for assets1.outre.ml. However, the client area doesn’t really tell you correctly which values to enter there. I’ve actually told someone else about this a couple of days ago, maybe this helps you too?

Cannot add a cname for my subdomain

You can get the SSL certificate on the subdomain, but the interface in the client area doesn’t show Record Name and Domain correctly. If you select the top level domain in the CNAME domain, and then add your subdomain to the record name with a dot, you should be able to add the CNAME record. So you can add the CNAME records for _acme-challenge.forum and _acme-challenge.www.forum with the destination as shown in the client area. I’ll write a bug report to fix this issue for subdomains.

[mmaismma]

Hmm. Looks like you are wrong. I have managed to get an SSL certificate on my subdomain using the method in Admin’s answer.
It should be noted that https is now working on my mentioned subdomain.

[Admin]

SSL on subdomains of your own domain is supported. SSL on subdomains of our domain (like epizy.com or rf.gd) is hard because almost no SSL vendor will let you get a certificate for it.