Iam not able to create user eventhough iam a admin for my portal

Iam not able to create user eventhough iam a admin for my portal

Hai Team,

I'am not able to add user my email id is " chandu@hash1919.com"  "You do not have permissions to create this account in Zoho Mail. Reach us at support-as@zohocorp.com for further assistance."  this error msg are showing even i'm a administrator. pls do resolve this issue ASAP

Thanks & Regards,
Chandu