Trying to remove a particular array value from an object. But it is not working. How to remove a array value from an object. If anyone knows please help to find the solution.

app.component.ts:

  public obj = {
    test1: ['j23', 'k54', 'm56'],
    test2: ['j29', 'k34', 'm59'],
    test3: ['j73', 'k94', 'm26'],
  };

 ngOnInit(): void { 
    delete this.obj['test1']['k54']; 
    console.log(this.obj);
 }

Demo: https://stackblitz.com/edit/angular-ivy-ekhxjo?file=src%2Fapp%2Fapp.component.ts