ValueError: Layer model expects 2 input(s), but it received 3 input tensors. Inputs received

Question

前提・実現したいこと

python3.8
tensorflow2.4
を使用しています
https://qiita.com/yutaoba/items/6eb0e12ba0d169a480df
上記のサイトを参考に画像キャプション生成を行っています。
しかし、エラーが発生しわからない状態です。
申し訳ございませんがご教示いただけないでしょうか。

発生している問題・エラーメッセージ

Traceback (most recent call last):
  File "/home/limlab/deep_learning/keras_imagecaption/japa_p3.py", line 419, in <module>
    tr.TrainModel()
  File "/home/limlab/deep_learning/keras_imagecaption/japa_p3.py", line 339, in TrainModel
    self.model.fit_generator(generator, epochs=self.epochs, steps_per_epoch=steps, verbose=1)
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/keras/engine/training.py", line 1847, in fit_generator
    return self.fit(
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/keras/engine/training.py", line 1100, in fit
    tmp_logs = self.train_function(iterator)
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/eager/def_function.py", line 828, in __call__
    result = self._call(*args, **kwds)
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/eager/def_function.py", line 871, in _call
    self._initialize(args, kwds, add_initializers_to=initializers)
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/eager/def_function.py", line 725, in _initialize
    self._stateful_fn._get_concrete_function_internal_garbage_collected(  # pylint: disable=protected-access
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/eager/function.py", line 2969, in _get_concrete_function_internal_garbage_collected
    graph_function, _ = self._maybe_define_function(args, kwargs)
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/eager/function.py", line 3361, in _maybe_define_function
    graph_function = self._create_graph_function(args, kwargs)
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/eager/function.py", line 3196, in _create_graph_function
    func_graph_module.func_graph_from_py_func(
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/framework/func_graph.py", line 990, in func_graph_from_py_func
    func_outputs = python_func(*func_args, **func_kwargs)
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/eager/def_function.py", line 634, in wrapped_fn
    out = weak_wrapped_fn().__wrapped__(*args, **kwds)
  File "/home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/framework/func_graph.py", line 977, in wrapper
    raise e.ag_error_metadata.to_exception(e)
ValueError: in user code:

    /home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/keras/engine/training.py:805 train_function  *
        return step_function(self, iterator)
    /home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/keras/engine/training.py:795 step_function  **
        outputs = model.distribute_strategy.run(run_step, args=(data,))
    /home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/distribute/distribute_lib.py:1259 run
        return self._extended.call_for_each_replica(fn, args=args, kwargs=kwargs)
    /home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/distribute/distribute_lib.py:2730 call_for_each_replica
        return self._call_for_each_replica(fn, args, kwargs)
    /home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/distribute/distribute_lib.py:3417 _call_for_each_replica
        return fn(*args, **kwargs)
    /home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/keras/engine/training.py:788 run_step  **
        outputs = model.train_step(data)
    /home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/keras/engine/training.py:754 train_step
        y_pred = self(x, training=True)
    /home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/keras/engine/base_layer.py:998 __call__
        input_spec.assert_input_compatibility(self.input_spec, inputs, self.name)
    /home/limlab/.local/lib/python3.8/site-packages/tensorflow/python/keras/engine/input_spec.py:204 assert_input_compatibility
        raise ValueError('Layer ' + layer_name + ' expects ' +
    ValueError: Layer model expects 2 input(s), but it received 3 input tensors. Inputs received: [<tf.Tensor 'IteratorGetNext:0' shape=(None, None) dtype=float32>, <tf.Tensor 'IteratorGetNext:1' shape=(None, None) dtype=int32>, <tf.Tensor 'IteratorGetNext:2' shape=(None, None) dtype=float32>]

該当のソースコード

    def DataGenerator(self):
        """
        ・model.fit_generatorに読み込ませるデータジェネレータを作成する。
        """
        while 1:
            for key, image_texts in self.train_texts_dict.items():
                image_feature = self.train_features_dict[key][0]
                in_img, in_seq, out_word = self.MakeInputOutput(image_texts, image_feature)
                yield [[in_img, in_seq], out_word]
                

  def TrainModel(self):
        """
        ・モデルを訓練する。
        """
        self.MakeTokenizer()
        self.GetVocabSize()
        self.GetMaxLength()
        self.MakeCaptioningModel()

        steps=len(self.train_texts_dict)
        for i in range(self.epochs):
            generator = self.DataGenerator()
            self.model.fit_generator(generator, epochs=self.epochs, steps_per_epoch=steps, verbose=1)
            self.model.save('model_' + str(i) + '.h5')
        return None