Unusual sending activity detected

Unusual sending activity detected

Hi there,
I'm a Sales and Marketing Associate, and I was trying to send marketing emails to potential clients.
I didn't know the email system would block merging mail. 
I'm sorry about this, and now I cannot send email anymore. 
To make my work normally, can I get unblocked as soon as possible?
I will not use merging email function in Word anymore.

Thanks,