Error when running run_dien.py

After installation of DeepCTR via python setup.py install, I get the following error:

cuda ready...
cuda:0
Train on 4 samples, validate on 0 samples, 2 steps per epoch
0it [00:00, ?it/s]
Traceback (most recent call last):
  File "run_dien.py", line 68, in <module>
    history = model.fit(x, y, batch_size=2, epochs=10, verbose=1, validation_split=0, shuffle=False)
  File "/home/erlebach/anaconda3/envs/torch/lib/python3.8/site-packages/deepctr_torch-0.2.8-py3.8.egg/deepctr_torch/models/basemodel.py", line 245, in fit
  File "/home/erlebach/anaconda3/envs/torch/lib/python3.8/site-packages/torch/nn/modules/module.py", line 1102, in _call_impl
    return forward_call(*input, **kwargs)
  File "/home/erlebach/anaconda3/envs/torch/lib/python3.8/site-packages/deepctr_torch-0.2.8-py3.8.egg/deepctr_torch/models/dien.py", line 92, in forward
  File "/home/erlebach/anaconda3/envs/torch/lib/python3.8/site-packages/torch/nn/modules/module.py", line 1102, in _call_impl
    return forward_call(*input, **kwargs)
  File "/home/erlebach/anaconda3/envs/torch/lib/python3.8/site-packages/deepctr_torch-0.2.8-py3.8.egg/deepctr_torch/models/dien.py", line 220, in forward
  File "/home/erlebach/anaconda3/envs/torch/lib/python3.8/site-packages/torch/nn/utils/rnn.py", line 249, in pack_padded_sequence
    _VF._pack_padded_sequence(input, lengths, batch_first)

Any help is appreciated.

Reproduce the failure with run_dien.py, especially line 68, then inspect deepctr_torch/models/dien.py at line 220 and the PyTorch pack_padded_sequence call. The report ends before the exception message, so capture the complete error and determine whether the input lengths or other arguments cause the failure; done means the example runs successfully.