Ocr Trainer error for custom font

i am trying to use ocr trainer https://www.mathworks.com/help/vision/ug/train-optical-character-recognition-for-custom-fonts.html#bu5hx2w-4 but whenever i press train i get error Internal error using tesseract error:NULL cluster! can anyone please help with this

[Makgola Thulare]

Hi, have you managed to resolve this?