Is it not possible to use interest groups when playing from one pc?

Interest groups are working for me with 2 players but not with 3 or more. The first and second player can see the third player and the third player can see the other ones. But the third player is not capable of sending via interest groups (except 0) with raise event. There is no error in console when trying to send something via interest group 105 as the third player with the unity engine. There is no error in the console when having the other perspective (first and second player). I'm starting the game 3 times on my pc. It doesn't matter whether I'm starting the build 3 times or using the editor. It doesn't matter whether the third player is started via build or via the editor. Since its the same script on every player and its working for the first and second perfectly with interest groups it isn't the usual mistake like don't writing PhotonNetwork.SetInterestGroups(106, true); or don't writing
RaiseEventOptions Raise = RaiseEventOptions.Default;
Raise.InterestGroup = 106;
PhotonNetwork.RaiseEvent(106, postemp, true, Raise);
or dont using the event code corretly. The third player can send messages with Raise.InterestGroup = 0; or with the right target actors just fine. I'm trying to find a mistake by my self since a few days and I even created a new project to see if the same error would occur and it did. Is it not possible to use interest groups when playing from one pc? I'm thankful for any help.