The shorter the "activation" phrase, the more prone it is to false activation. I successfully programming it to activate off of " hey moto" but it was going off all the time in my truck while listening to the radio. "OK Google" was much better, but still regularly activated during normal conversations with friends. "OK Google now" is the best... It may trigger once a day while having conversation with friends or family, but that's it.
What do you currently have it trained as? I would first retrain it, if that failed, then uninstall the update and reinstall, again If that fails, wipe cache and reinstall the update to touchless... All else fails, back up your apps and data and restore to stock then restore apps/data and set up touchless again.
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