Hi Mario,
What is the application note that you are working on?
I use "JN-AN-1217-Zigbee-3-0-Base-Device" project, and JN-SW-4170-Zigbee-3.0-v1518 SDK
Do you have the sniffer log of this issue?
I do not got the sniffer log.
Do you have only end devices?
there is only coordinator and end device.