Pomodoro Clock : decrement/increment tests failing

1

Although I can visibly see that my decrement and increment buttons are functioning as intended, the tests are failing. I could not be using a best practice and/or be failing to see something. Could anybody elaborate on why these tests are failing? Also, this is very much still a work in progress and not complete. Thanks in advance!

let clock;

class App extends React.Component {
  constructor(props){
    super(props)
    this.state ={
      breakLength: 5,
      sessionLength: 25,
      timeRemaining: 25 * 60,
      timer: this.setTimer(25*60),
      isStarted: false
    }
    this.initialState = this.state
    this.handleChange = this.handleChange.bind(this);
    this.handleStart = this.handleStart.bind(this);
    this.handleRestart = this.handleRestart.bind(this);
    this.setTimer = this.setTimer.bind(this);
    this.startTimer = this.startTimer.bind(this);
  }
  
  handleChange = (label, value) => {
    if(label === "break") {
        this.setState({
          labelLength: this.state.breakLength + value
        })
    }
        if(label === "session") {
        this.setState({
          sessionLength: this.state.sessionLength + value
        })
    }
  }
  
  handleStart() {
      if(this.state.isStarted){
      $("#start_stop").html("Start");
      this.setState({
        isStarted: false
      })
      clearInterval(clock)
    } else {
      $("#start_stop").html("Stop");
      this.setState({
        isStarted: true
      })
      this.startTimer()
    }
  }

  handleRestart() {
    clearInterval(clock)
    this.setState(this.initialState)
  }
  
  setTimer(remainingTime) {
    let minutes = Math.floor(remainingTime / 60);
    let seconds = remainingTime % 60;
    minutes = minutes < 10 ? "0" + minutes : minutes;
    seconds = seconds < 10 ? "0" + seconds : seconds;
    let timer = minutes + ":" + seconds;
    return timer.toString()
  }

  startTimer() {
      clock = setInterval(() => {
        this.setState({
          timeRemaining: this.state.timeRemaining - 1,
          timer: this.setTimer(this.state.timeRemaining - 1)
        })
      }, 1000)
  }
  
  render() {
    return (
      <div id="parent">
        <div id="label-section">
          <button id="break-decrement" onClick={() => this.handleChange("break", -1)} disabled={this.state.breakLength === 1}>Bd</button>
          <div id="break-label">Break Length</div>
          <div id="break-length">{this.state.breakLength}</div>
          <button id="break-increment" onClick={() => this.handleChange("break", 1)} disabled={this.state.breakLength === 60}>BI</button>
          <button id="session-decrement" onClick={() => this.handleChange("session", -1)} disabled={this.state.sessionLength === 1}>SD</button>
          <div id="session-label">Session Length</div>
          <div id="session-length">{this.state.sessionLength}</div>
          <button id="session-increment" onClick={() => this.handleChange("session", 1)} disabled={this.state.sessionLength === 60}>SI</button>
        </div>
        <div id="timer-section">
          <div id="timer-label">Session</div>
          <div id="time-left">{this.state.timer}</div>
          <button id="start_stop" onClick={this.handleStart}>Start</button>
          <button id="reset" onClick={this.handleRestart}>Reset</button>
        </div>
      </div>
    );
  }
}

ReactDOM.render(<App />, document.getElementById("app"));