According to News1 on February 6, 'Idol Producer' used the song "All Day" without proper authorization. The mission song from 'The Unit' was played during Yuehua Entertainment trainees' entrance on the Chinese show. 

SEE ALSO: Watch 'Music Bank' Live feat. TXT, NCT DREAM, ILLIT, ENHYPEN & more!

However, producers of 'The Unit' confirmed 'Idol Producer' did not properly seek for permission and the use of "All Day" is unauthorized. 

'Idol Producer' has already been involved in a plagiarism controversy for blatantly copying Korea's 'Produce 101'. Netizens are continuing to criticize the show for ongoing plagiarism, commenting, "Wow... I thought they purchased copyright but it was just stealing", "?? It's so similar. I thought it was a remake", "They copy everything -.-"