Email wrapper editing ?

Hello

Members who follow any thread receive a daily and weekly e-mail send known as Daily Digest emails. If we ban some members from the forum or this thread. Even then they receive the update post of this email bomb forum. In this way they get the updates of this thread even though they do not have it. I don't want them to send these emails. Or if they do, they don't include new forum posts. Tell me, how is that possible? How can an Email wrapper be edited because I don't understand much of the code there ? please reply