I get it all the time on my 2020 iPhone SE, even after several hours plugged into the car. I've come to hit "Emergency Override" if I know it's not been around

I get it all the time on my 2020 iPhone SE, even after several hours plugged into the car. I've come to hit "Emergency Override" if I know it's not been around moisture in the last few hours. Pity, because I wanted to hand this one on to an older relative in a few months, but I'm not about to saddle her with this.