I was using smartthings multisensor contact sensor to trigger an alexa routine announcement. It worked flawlessly 100% of the time for several months. Then, along came the smartthings update. All of a sudden, it takes numerous times (10-20) opening and closing the sensor to trigger the alexa routine. Both the ST app and Alexa app used to show the sensor closing every time it was activated. Since the update, alexa shows it working only sporadically. In frustration, I opened and closed the sensor 15 times quickly and nothing happened. Then, about 30 seconds later, it finally triggered the routine… and the routine repeated 15 times!! I tried it several times more and nothing. I think the update messed up the communication between the Alexa app and SmartThings app. If so, please fix it!!
I have the same problem! sometimes I get the announcement several minutes after the event and most times do not get the announcement! Really distressing!
Many people are being affected by this, although in somewhat different ways. It’s extremely frustrating. 
Smartthings engineering is aware of it and is working on it, but no timeline has been given for a fix.
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