The username which you have entered belongs to a different deployment/region

The username which you have entered belongs to a different deployment/region

HI,

I am trying to create a email for my business account ( www.theworldofjewellery.com) .when  i tried to signup with the above domain i am getting following error

 " The username which you have entered belongs to a different deployment/region"

Please help to resolve this asap.