Interaction for multiplayer via two switches not possible across the Internet

I want to Player on my World with frends online on my Switch but with the new Version (Bedrock Codebased) it dosn´t work. My Frend want to connect to my World, in the Multiplayertap my world is he seeing but when he want to join it dons´t work, connecion about. When I want to Join him the Same thing. We are connectet with Xbox Live and Nintendo to Join other, it works only by Win10 Minecraft via our Switch, to a World in Singelplayer who Online is on. Then we can Join, from switch to switch Multiplayer over the Internet it dosn´t work why ever.

And the Settings from Our Worlds to player with other are correct it means that Frends from Frends can Join and he is my Frend at Xbox Live and in our switches. Plus my Switch frends are not seen to Join in the Version of them.

What we tried:

• delete the the Game from the switch and downloard again

• try a nother world to join, only with win10 edition worked

• build a new one

• disconect and connect a new xbox Live account

• we have both nintendo switch online

• try to join to his world on his switch

• tryed since 1.5.1.2 bedrock

That World where I want to play is from Minecraft switch version pass on. And jesterday It seen that we can play, but my frend told me I was connecting and disconnecting by them and than connection about again.