Hi Fedir,
I have issue with OTA Upgrade for second device with the same firmware, as first.
I am no sure if I am getting your issue.
-Your Zigbee Network has 3 devices, coordinator and end devices(support OTA update)
-You updated the first device, and it works.
-Then, you try to update the second device, and it fails.
Is this the process that you are trying to do?
how to configure OTA upgrade for 2 and more simultaneous devices?
You have to options
-Broadcast
-Create a group with the devices and update.
Regards,
Mario