laravel post via jquery ajax "MethodNotAllowedHttpException"

I have this html in my view. when I submit the form in bootbox via jquery.ajax I get "Method not allowed". I don't know what is wrong with my code.

                       
                                {!! Form::open(array('id'=>'form1','class'=>'form-horizontal','style'=>'display:none;')) !!}


                 <div class="form-group">
                     <label class="col-xs-3 control-label">Name</label>
                     <div class="col-xs-5">
                         <input type="text" class="form-control" name="fullname"  value="{{ $user->name }}"/>
                     </div>
                 </div>

                 <div class="form-group">
                     <label class="col-xs-3 control-label">Age</label>
                     <div class="col-xs-5">
                         <input type="text" class="form-control" name="age" value="{{ $user->age }}" />
                     </div>
                 </div>



             {!! Form::close() !!}

here is my js

   $('#mybutton').on('click,function(e){
              e.preventDefault();

            bootbox.dialog({
                   message: $('#form1'),
                   title: "form",
                   buttons: {

                       danger: {
                           label: "Cancel",
                           className: "btn-danger",
                           callback: function() {
                               $('#form1').hide().appendTo('body');
                           }
                       },
                       main: {
                           label: "Submit",
                           className: "btn-primary",
                           callback: function() {
                               $.ajax({
                                  type:'POST',
                                  dataType:'text',
                                  data:{name:name,age:age},

                                  url:'addstudent',
                                  success:function(data){

                                      console.log(data);


                                  }

                               });




                           }
                       }
                   }
               })
                   .on('shown.bs.modal', function() {
                       $('#form1')
                           .show()

                   });         


   });

and my route

Route::post('register/addstudent', [
    'as' => 'addstudent', 'uses' => 'Admin\StudentController@addstudent'
]);

via Chebli Mohamed