Unable to send message: Reason 550 5.4.6 mail rate exceeded limit

Unable to send message: Reason 550 5.4.6 mail rate exceeded limit

Hi,


one of my user is unable to send messages. He is getting message he cannot send.

Error: Unable to send message: Reason 550 5.4.6 mail rate exceeded limit

User Email id: ahmad@click2clinic.com

Kindly revert asap

Saikumar.K