Custom CNAME but blocked

I’m trying to setup a domain proxy.domain.com that users can point their domain to via CNAME (for simple use) then I verify that that domain is pointed to the vps, if so I create a reverse proxy for the user that will display their custom stuff on their domain. But the problem is I keep getting this error when people do this. This has seemed to occur when I implemented a *.frostproxy.com (wildcard domain) into my DNS settings. To get around this issue would I need to go to the vps that has this wildcard domain and reverse proxy that domain to my other vps where I want the user pointing to? Or do I need to purchase PRO for one god dam month and submit a single ticket to resolve this issue?

**Error 1014 Ray ID **

CNAME Cross-User Banned
What happened?
You've requested a page on a website that is part of the Cloudflare network. The host is configured as a CNAME across accounts on Cloudflare, which is not allowed by Cloudflare's security policy.

What can I do?
If this is an R2 custom domain, it may still be initializing. If you have attempted to manually point a CNAME DNS record to your R2 bucket, you must do it using a custom domain. Refer to R2's documentation for details.