Why is the video collected in the python exe file not saved when recording via opencv?

Question

Python

Created a program for collecting dataset. In it, a person must perform certain actions, and this is recorded on video. I record the video like this:

fourcc = cv2.VideoWriter_fourcc(*'XVID')
#width и height - это соответственно ширина и высота кадра
recorder=cv2.VideoWriter("cam0.avi", fourcc, 25, (width,height))
cam=cv2.VideoCapture(0)
success,frame=cam.read()
recorder.write(frame)
cap.release()
recorder.release()

In the code, of course, everything is more complicated, but you get the point. This whole system works great when run through a py file or from a Jupyter Notebook. However, to distribute this program, I compiled it into an exe file using pyinstaller. The program works as it should, but the recorded videos are empty (take up 0 bytes and are not played). What is the problem?