pocketsphinx thowing NoneType error while stitching samples

[pporanki]

while runing training.run.stitch_vocab_samples gave a error after few 1-10 training.wav files generation

File "/home/nsl/asr/howl/howl/utils/sphinx_keyword_detector.py", line 25, in detect
result = phrase.segments(detailed=True)
File "/home/nsl/.local/lib/python3.8/site-packages/pocketsphinx/init.py", line 134, in segments
return [
TypeError: 'NoneType' object is not iterable

Could you please help with issue here