Widget Interaction with Event Dispatcher doesn't work


I’ve got a problem with a widget button: By pressing the button the widget (BP_Menu) calls an event dispatcher.
The ‘Listener’ (BP_Schalter) has got the defined Custom Event (Toggle_Licht) and is binded to the event dispatcher.
But the Custom Event doesn’t start, when I press the widget button.

Here is the Blueprint Runtime Error Message:
Accessed None trying to read property BP_Menu from function: ‘ExecuteUbergraph_BP_Schalter’ from node: Bind Event to ED_LightToggle in graph: EventGraph in object: BP_Schalter with description: Accessed None trying to read property BP_Menu

Here are some screenshots to clarify the situation:

Any idea? Many thanks for every reply in advance!
Best regards. Andrejowitsch

Sorry for the confusion I did a mistake with the picture.

Here is the correct one:

Hello! Did you solve this issue? Im strugling with that issue right now.

Hi, yes I solved that issue, but not with the ‘EventDispatcher’. I defined a ‘CustomEvent’ in the BluePrint of the LightObject and started it with the function ‘GetAllActorsOfClass’ from the LightButtonObject-BluePrint. I hope that helps!
Best regards.

Thank you for your answer. But in my situation only event dispatcher would work and im trying to make it work.