public signInInteraction: boolean = true;

 this._loginService.loginUser(JSON.stringify(this.loginUser))
        .subscribe((data) => {          
          this.signInInteraction = true;
          this.navHome();
        },
        (error) => {        
          console.log(this.password)
          this.signInInteraction = true;
          this.isLoginApi = true;
        });

 <Button id="btnSubmit" text="Sign in" [isUserInteractionEnabled]="signInInteraction" class="Loginsubmit" autocapitalizationType="none" (tap)="Login()"></Button>