setInterval refreshes the app instead of updating the state

I'm coding a countdown with Expo. I'm using functional components, so my state is handled via React's useState hook.

let [state, setState] = useState({
    secondsLeft: 25,
    started: false,
});

If I press a Button it does fire this function:

let onPressHandler = (): void => {
    if(!state.started) {
        setState({...state, started: true});
        setInterval(()=> {
            setState({...state, secondsLeft: state.secondsLeft - 1});
            console.log(state.secondsLeft);
        }, 1000);
    }
}

Problem is that each 1000 ms Expo refreshes the app instead of updating the state.

Can you help me, please?