You can cancel a mailing within 1 Hour of clicking "Start Mailers."
After that, the mail will be printed and dropped in the mail. Once that happens, just like dropping mail into the post office mail box, you can't reach back in and get it out!
If you start mailers by mistake, you should see an undo button to stop it right away.If you don't, just open the lead and click pause mailers.
Now if it has already been more than an hour... it’s already sent.