On January 5 KST, IU has updated her Instastory with a screenshot of the SBS' 'Unanswered Questions' uncovering "sajaegi"(means bulk buying in Korean, usually refers to the act of manipulating streaming charts).  

'Unanswered Questions' uncovered issues surrounding "sajaegi" on January 4 at 11 PM KST. In the captured snippet of 'Unanswered Questions', it reads "I then realized why people do sajaegi". In the caption, above the screenshot, IU wrote, "But don't do it, please." 

IU has been a strong contender in every streaming platforms' charts for more than a decade. As a veteran in the industry, her remark shows the magnitude of this issue and is a warning towards those who have been considering "saejagi" or other forms of malicious viral marketing.