json.decoder.JSONDecodeError: Expecting value: line 15 column 3 (char 33)

[kunsungwoo]

line 52, in load_data df = fdr.StockListing(market) line 355, in raw_decode raise JSONDecodeError("Expecting value", s, err.value) from None json.decoder.JSONDecodeError: Expecting value: line 15 column 3 (char 33)

NASDAQ works, but KRX, KOSDAQ, and KOSPI have problems. What is the problem??