Why Laravel controller store() inserts null values into DB

I want to insert data into a table MySQL database through the controller store function, but it always inserts null values. I don't know where the problem is.

Model

class Office extends Model
{
    protected $fillable = array('office_name_local', 'office_english_name');
}

Controller

public function store(Request $request)
{
    $validatedData = $request->validate([
        'office_name_local' => 'required', 'office__name_english' => 'required'
    ]);

    $office = Office::create($validatedData);

    return redirect('/createOffice')->with('success', 'Office is successfully saved');
}

Blade

<form method="POST" class="form-horizontal well col-xs-8 col-xs-offset-2"
      action="">
    <div class="form-group row">
        <div class="col-md-6">
            <label for="office_name_local"> local name</label>
            <input type="text" class="form-control" name="office_name_local" required>
        </div>
    </div>
    <div class="form-group row">
        <div class="col-md-6">
            <label for="office_name_english"> English name</label>
            <input type="text" class="form-control" name="office_name_english" required>
        </div>
    </div>
    <div class="form-group row mb-0">
        <div class="col-md-6 offset-md-4">
            <button type="submit" class="btn btn-primary">
                
            </button>
        </div>
    </div>
</form>   

via Chebli Mohamed