Arbitrary invocation of Siri on Mac?

Question

macOS

Hello.
It happens that you move away from the laptop, you do nothing for about 5 minutes, the screen does not go out at this time and for some reason Siri is spontaneously called. Recently, through dictation , I set up Siri to respond when I say hello to Siri. But I didn't want to randomly call her. Has anyone had this, how can I fix it?