Restoring to the Computername to the previous helped! It works 100%
My Computername changed, because I restored it with time Machine to another Device and there was a conflict. So I had "Macbook" and "Macbook (1)" as a Computername on my both Devices.
I changed the name back to "Macbook" on my Macbook Pro and it works easily.
I got a popup message telling, that I use this plugin for the first time after the new update of Helix Native. This is wrong, I used it may times after the Update, but the plugin didn't recognise it because it's somehow fixed to the computer name.