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, our email prensa@inbestme.com has been blocked and we see the following error when we attempt to send an email.

Unable to send message; Reason: 550 5.4.6 Mail rate exceeded limit.

Today we use this email to send emails to the press and because of this the activity of the email may appear suspicious. I would like to confirm that it is all correct. Please, could you unblock the email.