SMB other user cannot access folder

[SpaghettiDemon]

I have a share for my family to use as a Network storage.
When i create a folder the user of my father cannot access it.
This is unidirectional as when my father creates a folder i can access it with my user.

 

I do not think this is a Windows Problem.
Things i tested:
Creating folder with my user on my Laptop running Linux => my father cannot access
Creating folder with my fathers user on my Laptop running Linux => i can access

Creating folder on my fathers PC running Win10 => i can access

Creating folder on my PC running Win10 => my father cannot access

Connected as my fathers user on my Laptop => cannot access folders created by my user 

Deleted and recreated my fathers user

 

When listing the folders (uwe = my father, simon = me):

 

We have the same access rights and the same group, why does he not have permissions?

Already tried several things, only temporary fix is running the new Permission tool.

 

Hoping someone can help me as i have no idea why it is not working