Error setting primary domain

vendor-ping.netlify.app is my netlify subdomain
vendor-ping.windsurf.build is my current primary domain
I purchased a domain from namecheap, vendorping.ai - I successfully added it as an alias, switched the nameservers. and it resolves my site.
However I am trying to set it as the primary domain and I get the following error.

domain_aliases must be unique (conflicting alias) (vendor-ping.windsurf.build, 83048dd0-42bc-42e9-882e-54a9a2903bed):vendor-ping, is owned by another account

I’ve sent this to the helpdesk. You should hear back soon.