Model.fit Value Error (Text Classification Model) - python-3.x

Question

I need your help please...
I am trying go get the following Text Classification Module working:
# Train and validate model.
history = model.fit(x_train,
train_labels,
epochs=epochs,
callbacks=callbacks,
validation_data=(x_val, val_labels),
verbose=2,
batch_size=batch_size) # Logs once per epoch.
Source File Can be Found Here: Google - Git Hub Text Classification Code
However I am getting the following error on execution:
Traceback (most recent call last):
File "train_ngram_model.py", line 113, in <module>
train_ngram_model(data)
File "train_ngram_model.py", line 93, in train_ngram_model
batch_size=batch_size) # Logs once per epoch.
File "C:\Users\joebloggs\AppData\Roaming\Python\Python37\site-packages\tensorflow_core\python\keras\engine\training.py", line 819, in fit
use_multiprocessing=use_multiprocessing)
File "C:\Users\joebloggs\AppData\Roaming\Python\Python37\site-packages\tensorflow_core\python\keras\engine\training_v2.py", line 235, in fit
use_multiprocessing=use_multiprocessing)
File "C:\Users\joebloggs\AppData\Roaming\Python\Python37\site-packages\tensorflow_core\python\keras\engine\training_v2.py", line 593, in _process_training_inputs
use_multiprocessing=use_multiprocessing)
File "C:\Users\joebloggs\AppData\Roaming\Python\Python37\site-packages\tensorflow_core\python\keras\engine\training_v2.py", line 646, in _process_inputs
x, y, sample_weight=sample_weights)
File "C:\Users\joebloggs\AppData\Roaming\Python\Python37\site-packages\tensorflow_core\python\keras\engine\training.py", line 2383, in _standardize_user_data
batch_size=batch_size)
File "C:\Users\joebloggs\AppData\Roaming\Python\Python37\site-packages\tensorflow_core\python\keras\engine\training.py", line 2428, in _standardize_tensors
converted_x.append(_convert_scipy_sparse_tensor(a, b))
File "C:\Users\joebloggs\AppData\Roaming\Python\Python37\site-packages\tensorflow_core\python\keras\engine\training.py", line 3198, in _convert_scipy_sparse_tensor
raise ValueError('A SciPy sparse matrix was passed to a model '
ValueError: A SciPy sparse matrix was passed to a model that expects dense inputs. Please densify your inputs first, such as by calling `x.toarray()`.
I have spent several hours now to find a solution, and I haven't gotten anywhere.
Thank you in advance for your reply.