Sneaking into my phone!

So apparently someone keeps trying to get in my phone and putting in the wrong passcode! How do I know U ask? Because every morning now for the past 2 weeks, my phone tells me I need to type in my passcode and the finger print won't work! My children are way too young and sleep all night! I do have a nosey husband! I've seen him in action but never with my phone!  What should I do ? Confront him, or let it keep happening?