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I have a site http://142.93.112.185/ written in Laravel 5.8 When you double click on my name, a sign-in form will come up

does not matter what I put into the form, after submit I kept getting this.

What cause this ? I've tried to put dd("HERE") in my controller, I can't even get it to display.

public function postSignIn()
{

    dd("HERE");
    ...
}

Any hints for me ?

---

HTML

<form action="/" method="POST" name="signinForm">
    {!! csrf_field() !!}

    <p style="color: red;" ng-show="signinForm.username.$invalid && signinForm.username.$touched"> Invalid Email/Username
    </p>

    <div class="form-group">
        <label for="username">Email</label>
        <input type="email" class="form-control"  id="username" name="username" placeholder="Enter Username" ng-model="username" ng-required="true"
        >
    </div>


    <div class="form-group">
        <label for="password">Password</label>
        <input type="password" class="form-control" id="password" name="password" placeholder="Enter Password" autocomplete="off"
        ng-model="password" ng-required="true"
        >
    </div>

    <div class="login-buttons"  >
        <button type="submit" class="btn btn-primary btn-block " ng-disabled="signinForm.username.$invalid || signinForm.password.$invalid">Log in</button>
    </div>

</form>

via Chebli Mohamed