"Janie Jones" is a song by the English punk rock band The Clash. It is the opening track on their eponymous debut album (1977). The subject of the song, Janie Jones, was a famous madam in London during the 1970s and had been a pop singer during the 1960s.
Janie Jones was a madam in the 1960s.
Due to the fact that Janie Jones was actually a madam in the 1970s, but a singer in 1960s and this was in one sentence in the statement, I believe it made it hard for the system to recognize the difference of the dates of the occupations.