In this post Original & Aqara Xiaomi Zigbee Sensors (contact, temp, motion, button, outlet, leak, etc) that “SmartThings has not yet published developer documentation on how to do this (use the Handler Device), so the best solution is to use the SmartThings “Classic” mobile app for now”.
Seriously?
If that problem exists, I find it complicated to move on to the new application of smartthings, although it is true that I have three Xiaomi devices and they work correctly in the new application.
Greetings.