Unable to purchase new domain for my website

Unable to purchase new domain for my website

Hello, 

I've fully edited my site. .When it was ready to publish The domain cant be purchased..


Shows

 Reason: Sorry , we are unable to process your request, please contact support@zohomail.com 


Yesterday I've published with a free sub domain... today I unpublished that and tried to purchase to publish with my own domain... But it shows like this..  And I cant even publish it with free domain...    How can I proceed to buy Please help...

Thank you.