Downgrading ios

Hi.

I'm a type 1 diabetic and use a Dexcom G6, a device that it attached to my body that continuously measure my blood sugar levels and sends that information to my iPhone. It seems that Dexcom don't make sure their devices are immediately compatible with the lastest iOS. My phone automatically updates iOS but this has caused problems as Dexcom isn't up to date. For instance, I have iOS 13.3, but Dexcom only supports up to iOS 13.2.0.

Is there a way I can easily downgrade to iOS 13.2.0 from iOS 13.3?

Thanks in advance!