device dies for the second time

[rob0t1704]

A Qubino ZMNHND1 Flush 1D relay+ module dies after a couple of weeks. It shows the red dot with the exclamation mark in the hardware tab. I have had the same problem a month ago and replaced the node.
I found it hard to believe that two equal devices in the same location (physically) stops working. They are not damaged and there's no reason why they stopped working. If I look at the zwave illustration I can see the node but no connection to an other node. I have attached a jpg file with the illustration. Is there a logical explanation?
It is node 26.