Microsoft Teams: How to prevent Teams echo bot from constantly disturbing phone conferences

Some people have found a new hobby: Blowing up Teams meetings.

How do they achieve this?

Very easy. If you are inside a Teams meeting just go to "add members" and type in "Teams echo":

The annoying things about this: 

• This can be done by anyone who was invited and is not limited to your organzation
• On Linux you are not able to invite the Team Echo
• The lobby does not work for Teams Echo - that means he will join you and you have to chance to get rid of that.
• You can not mute Teams Echo
  

Then click on this and you will get the following experience:

 

There is one hint i found:

https://docs.microsoft.com/en-us/answers/questions/284720/can-we-block-or-remove-39teams-echo39-bot-from-ent.html 

Microsoft itself does not really understand the issue:

https://answers.microsoft.com/en-us/msteams/forum/all/teams-echo-entering-into-meetings/3418d131-8619-4785-9ab4-0aed6acbb8c2?auth=1

But this does not work, because you do not find a "Teams echo app" inside https://admin.teams.microsoft.com/policies/manage-apps 

The problem is known:

If you know how to prevent this: Please leave a comment...