iPhone SE Turns Silent Mode Off Without My Knowledge

I have an iPhone SE (2020 model). I always keep the switch on the side flipped to silent mode because honestly I've never been in a situation where I absolutely need to hear my ring tone or text tone in case someone calls or messages me. The silent mode switch seems to be very sensitive; every couple of weeks or so, it will flip the switch and turn silent mode off, I guess from being jostled around in my pocket as I walk or something. It's always a little annoying, but I had an absolutely mortifying moment at uni today when my phone, I guess having flipped the switch yet again in my pocket without my notice, very loudly received a spam call and my prof decided to use me as an example for disrupting the class. I need to make sure this doesn't happen again. Is there anyway to make sure that the silent mode switch stays in place, or to override it so that my phone is always on silent mode regardless of how the switch is flipped?