"send email wizard" appear not working

Send email wizard appears not working on Version: ( LibreOffice Community
Build ID: 49f2b1bff42cfccbd8f788c8dc32c1c309559be0) on MAC OS.

I configured Mail merge, I configured SMTP server in LibreOffice preferences and tested connection. Everything is working fine and give me positive test.

When I click on “Send email wizard” it open the pop-up windows for chosing email and other option, it finds the proper headers of mails.
When click on send, it opens the windows sending with the right number of users mails I loaded in the DB, it sends and no error message.

The email never arrive to any user! It is as for Writer is sent while really is not.

Any idea?

Many thanks