Laravel 5.5: Increase time on multiple failed login attempts

In Laravel 5.5, currently five login attempts blocks user for 1 minute by default. I want to design such a system like:

1. After first 3 failed login attempt, block user for 2 minutes
2. After that, for the next 2 failed login attempt(that is total 5th time), block user for 5 minutes.

I have edited ThrottlesLogins.php file like:

public function maxAttempts()
{
    return property_exists($this, 'maxAttempts') ? $this->maxAttempts : 2;
}

public function decayMinutes()
{
    return property_exists($this, 'decayMinutes') ? $this->decayMinutes : 2;
}

And then in my LoginController.php file:

public function adminLogin(Request $request)
{
        $this->validate($request, [
            'email'   => 'required|email',
            'password' => 'required|min:6'
        ]);

        $key = $this->throttleKey($request);
        $rateLimiter = $this->limiter();

        //check if the user has too many login attempts.
        if ($this->hasTooManyLoginAttempts($request)){
            $attempts = $rateLimiter->attempts($key);
            $rateLimiter->clear($key);
            if($attempts === 5){
                $this->decayMinutes = 5;
            }

            for ($i = 0; $i < $attempts; $i++) {
                $this->incrementLoginAttempts($request);
            }

            $this->fireLockoutEvent($request);  //Fire the lockout event.
            return $this->sendLockoutResponse($request); //redirect the user back after lockout.
        }


        if (Auth::guard('admin')->attempt(['email' => $request->email, 'password' => $request->password],
            $request->get('remember'))) {

            return redirect()->intended('/admin');
        }

        //keep track of login attempts from the user.
        $this->incrementLoginAttempts($request);

        return back()->withInput($request->only('email', 'remember'));
}

I have already followed this: Stack Overflow

But it does not solve my problem. How can i achieve such system ? Any help ?

via Chebli Mohamed