Invalid SSL certificate for subdomain

I added a subdomain on CWP7, and then added an SSL certificate for this subdomain. It uses the same SSL certificate as the main domain. This subdomain also points to /home/domain/public_html which points to the same directory as the main domain.

Then add an A record for this subdomain in Cloudflare.

But when accessing this subdomain, Cloudflare prompts “Error 526， Invalid SSL certificate, Host Error” on the browser


I want to know how to fix it?

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