The 46-year-old star shot to fame as a member of the girl group. In recent years, she has declined reunion plans. Now, she has opened up about her reason while writing a letter to her future self in Britain's Vogue magazine
According to People Magazine, while speaking with Mendes as he covers VMAN magazine, the 73-year-old pop-icon John told the 'In My Blood' singer to be cautious of fame and letting the idea of celebrity get to his head.