Portfolio: can't disconnect domain from old portfolio to use on new one.

Hi,

I had previously added a custom domain to a Portfolio site that was on my then-employers account. I no longer work for the company and am now trying to use the same domain name on a new Portfolio in a new Adobe CC account.

When I try and connect the domain I get the following message: 

This domain is already connected to an Adobe Portfolio site

There is no option to disconnect the domain on this page or anywhere else. I have made sure that the DNS settings are pointing to Adobe, but it still seems to be recognising the domain from before and sending it to the 'site not found' page.

Please help as I desperately need to apply for jobs using the domain and my new Portfolio.