I am trying to figure out an issue for a coworker. Their Hey Siri has stopped functioning. They are running iOS11.3.1. So far we have tried rebooting the device as well as turning the feature off and back on, which required a re-training for Hey Siri. Any other suggestions of why the feature has stopped working. I personally don't use it and admit I'm a bit at a loss myself, but I'm sure others here do. Here's to hoping someone has a tip or trick my team and I have not yet though of.