My Siri keeps randomly opening, how do I stop this?

What you do is reset your iphone, by holding the home and lock button. If that does not work, you can change the settings to disable siri

I occasionally get Siri when I hold the Home button down instead of just clicking it. Check to see that you are using the .home button correctly. A click does one thing, holding it down calls up Siri.

Had a similar issue with Siri popping up randomly. Even went into the settings menue to turn Siri off. Voice control would come up instead. In my case, sometimes when I would try to turn off the iphone, it would snap a screen shot leading me to think the home button was somehow stuck. Long story short, had the Home button replaced at a cellphone repair shop for about $59 and my problem is now fixed.