Keep downloading deleted messages!

I connect Note 8 Client to my email box hosted by a hosting service provider! Note 8 Client keeps downloading the messages again and again after every time I have deleted the messages from within Note 8 Client.

How can I tune the Note Client or Domino Server as we do on other email client software so that the messages can be deleted on the 3rd party email box at the same time we delete them on our Note 8 Client?? Thanks!