25+5 Timer project

Everything works fine when I test manually., but there are so many failed tests. How should I fix?`

// !! IMPORTANT README:

// You may add additional external JS and CSS as needed to complete the project, however the current external resource MUST remain in place for the tests to work. BABEL must also be left in place. 

/***********
INSTRUCTIONS:
  - Select the project you would 
    like to complete from the dropdown 
    menu.
  - Click the "RUN TESTS" button to
    run the tests against the blank 
    pen.
  - Click the "TESTS" button to see 
    the individual test cases. 
    (should all be failing at first)
  - Start coding! As you fulfill each
    test case, you will see them go   
    from red to green.
  - As you start to build out your 
    project, when tests are failing, 
    you should get helpful errors 
    along the way!
    ************/

// PLEASE NOTE: Adding global style rules using the * selector, or by adding rules to body {..} or html {..}, or to all elements within body or html, i.e. h1 {..}, has the potential to pollute the test suite's CSS. Try adding: * { color: red }, for a quick example!

// Once you have read the above messages, you can delete all comments. 
class Timer extends React.Component {
  constructor(props){
    super(props)
  }
  state={break:5, session:25, timer:false, sessionRunning:true};
  interval=null; sessionTime=this.state.session*60; breakTime=this.state.break*60;
  
  
  displayTime=(time)=>{
    let min=parseInt(time/60); let sec=time%60; var displayMin, displaySec;
    if(min<10){displayMin=`0${min}`} else {displayMin=min};
    if(sec<10){displaySec=`0${sec}`} else {displaySec=sec};
    return `${displayMin}:${displaySec}`;
  }
  
  breakUp=()=>{
    if(this.state.break<60 && this.interval===null){
      this.setState({break:this.state.break+1});
     
    }
  }
  breakDown=()=>{
    if(this.state.break>1 && this.interval===null) {this.setState({break:this.state.break-1}); }
    
  }
  sessionUp=()=>{
    let timeLeftEle=document.getElementById('time-left');
    if(this.state.session<60 && this.interval===null){this.setState({session:this.state.session+1},()=>{
      timeLeftEle.innerText=this.displayTime(this.state.session*60);
    });}
  }
  sessionDown=()=>{
    let timeLeftEle=document.getElementById('time-left');
    if(this.state.session>1 && this.interval===null){this.setState({session:this.state.session-1},()=>{
      timeLeftEle.innerText=this.displayTime(this.state.session*60);
    });}
  }
  
  startPause=()=>{
    let timeLeftEle=document.getElementById('time-left');
    let beep=document.getElementById('beep');
    let timeLeft=timeLeftEle.innerText.split(":")[0]*60+timeLeftEle.innerText.split(":")[1]*1;
    let startStop=document.getElementById('start_stop');
    if(startStop.innerHTML==='<i class="fa-solid fa-play"></i>'){
      startStop.innerHTML='<i class="fa-solid fa-pause"></i>'
    } else {
      startStop.innerHTML='<i class="fa-solid fa-play"></i>'
    }
    if(this.interval===null){
      this.interval=setInterval(()=>{
        timeLeft--;
        timeLeftEle.innerText=this.displayTime(timeLeft);
        if(timeLeft<1 && this.state.sessionRunning){
          this.setState({sessionRunning:false});
          timeLeft=this.state.break*60;
          beep.play();
        } else if (timeLeft<1 && !this.state.sessionRunning){
          this.setState({sessionRunning:true});
          timeLeft=this.state.session*60;
          beep.play();
        }
      },1000)
    } else {
      clearInterval(this.interval);
      this.interval=null;
    } 
  }
  
  resetTime=()=>{
    let startStop=document.getElementById('start_stop');
    let beep=document.getElementById('beep');
    beep.pause();
    beep.currentTime=0;
    let timeLeftEle=document.getElementById('time-left');
    startStop.innerHTML='<i class="fa-solid fa-play"></i>';
    if(this.interval!==null){
      clearInterval(this.interval);
      this.interval=null;
    }
    this.setState({break:5, session:25, sessionRunning:true},()=>{
      timeLeftEle.innerText=this.displayTime(this.state.session*60);
    });
  }
  
  render(){
    return (
      <div id='wrapper'>
          <div id='description'>25+5 Clock</div>
          <div id='break' className='lengthWrapper'>
            <div className='title' id='break-label'>break length</div>
            <div className='length' id='break-length'>{this.state.break}</div>
            <div className='arrowWrapper'>
              <a className='arrow' id='break-increment' onClick={this.breakUp}><i class="fa-solid fa-arrow-up"></i></a>
              <a className='arrow' id='break-decrement' onClick={this.breakDown}><i class="fa-solid fa-arrow-down"></i></a>
            </div>
          </div>
          <div id='session' className='lengthWrapper'>
            <div className='title' id='session-label'>session length</div>
            <div className='length' id='session-length'>{this.state.session}</div>
            <div className='arrowWrapper'>
              <a className='arrow' id='session-increment' onClick={this.sessionUp}><i class="fa-solid fa-arrow-up"></i></a>
              <a className='arrow' id='session-decrement' onClick={this.sessionDown}><i class="fa-solid fa-arrow-down"></i></a>
            </div>
          </div>
          <div id='display'>
            <div id='timer-label'>{this.state.sessionRunning?'Session':'Break'}</div>
            <div id='time-left'>{this.displayTime(this.state.session*60)}</div>
            <audio id='beep' src="https://raw.githubusercontent.com/freeCodeCamp/cdn/master/build/testable-projects-fcc/audio/BeepSound.wav" preload='auto'>Cannot access the audio</audio>
            <div id='buttonWrapper'>
              <button id='start_stop' onClick={this.startPause}><i class="fa-solid fa-play"></i></button>
              <button id='reset' onClick={this.resetTime}>Reset</button>
            </div>
          </div>
      </div>
    )
  }
}
const root=ReactDOM.createRoot(document.querySelector('#root'));
root.render(<Timer />);

what is this, where is this executed? what should you do? what’s happening? what should happen instead?

Here is the project link.

I can definitely tell that the tests are not perfectly designed. In my previous calculator partice project, I notice some small bugs in the project but all the tests past.