Pomodro-clock stuck need help!

Tell us what’s happening:
I am building a pomodro clock app but i am stuck at here…when i hit the start, the countdown starts but again when i hit it wont clear the interval
Whats wrong in my code.please help me out

Your code so far

//state
class MyProvider extends Component {
  state = {
    session: 20,
    break : 5,
    isRunning : true,
  }
//show time method
showTimer: () => {
        let time = setInterval(startTimer,1000)
        this.setState({
          isRunning : !this.state.isRunning
        })
        this.state.isRunning ? console.log("hello") : clearInterval(time)

      },

Your browser information:

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