This Operation has been restricted. Please contact support@zohomail.com for further details

This Operation has been restricted. Please contact support@zohomail.com for further details

Hi,

I am trying to register a domain www.mmrsonline.com in zohomail, When I did the HTML option, "This Operation has been restricted. Please contact  support@zohomail.com for further details"

What is the reason for this message? I have done several domain verifications for my clients in the past using HTML method and didn't have any problem. 

Regards,
Edward