Subdomain starting with ns

Hi does Cloudfare support subdomains starting with ns? i.e or

We tried to set-up Cloudfare via the Plesk extension and it didn’t work as Plesk extension sees any subdomain that start with ns as invalid subdomain to proxy over Cloudflare. Will I face the same issue if sign-up for the business plan?

From Cloudflare’s DNS tab, I just added an A record for ns-test ( and it took it just fine.