Symfony\\Component\\HttpKernel\\Exception\\HttpException exception

I am facing "exception": "Symfony\Component\HttpKernel\Exception\HttpException" in my laravel file, here is my .ajax-jquery script:

$('#companyyear_form').on('submit', function(event){
            event.preventDefault();
            var company = $('#company').val();
            var checkbox_Names = new Array();
            $("input[name='month_year_multi_id[]']").each(function(){
                if($(this).is(':checked')&& $(this).is(':enabled')) {
                    checkbox_Names.push($(this).val());

                }

            });
            console.log(checkbox_Names);
            console.log(company);
           
            $.ajax({
                headers: {
                             'X-CSRF-TOKEN': $('meta[name="_token"]').attr('content')
                         },
                url: 'postcompanyyear',
                method:'POST',
                data: {
                    company:company,
                    checkbox_Names:checkbox_Names,
                },
                dataType: 'json',
                success: function(data)
                {
                    console.log(data);
                    $('#form_output').html(data.success);
                    $('#companyyear_form')[0].reset();
                    $('#action').val('Add');
                    $('.modal-title').text('Add Program');
                    $('#button_action').val('insert');
                },
                error:function(data)
                {
                    console.log(data);
                }


            })
        });

and here is my controller:

        public function postdata(Request $request)
{
    $month_year_multi_ids = $request->get('checkbox_Names');

    foreach ($month_year_multi_ids as $key => $value) {
        $last_space = strrpos($value, ' ');
        $year[] = substr($value, $last_space);
        $month[] = substr($value, 0, $last_space);
    }

    $validation = $request->validate([

        'company' => 'required',
        'checkbox_Names' => 'required',

    ]);

    $error_array = array();
    $success_output = '';


    if ($request->get('button_action') == "insert")
    {
        foreach ($month_year_multi_ids as $index => $values) {
            $company_year = new CompanyYear([

                'company_id'  => $request->get('company'),
                'year' => $year[$index],
                'month' => $month[$index],

            ]);
            $company_year->save();
        }


    }
    $success_output = '<div class="alert alert-success">Data Inserted</div>';

    $output = array(
        'errror' => $error_array,
        'success' => $success_output
    );
    echo json_encode($output);

}

and this is my postcompanyyear route:

Route::post('postcompanyyear','CompanyYearController@postdata');

may be the data is not passing, can you tell me, why I am getting the exception?? and also the solution.