Pattern more than badminton. Scammers posed as police asked victims to dial a set of number and install an app to monitor credit card transactions. This activated call forwarding to scammers. Scammers answered when bank calls victim number to ask about unusual transaction. OTP will get forwarded to scammer too.
https://tw.news.yahoo.com/新詐騙太兇-手機輸入-21-瞬間被接管-詐團兩天盜刷賣股得手366萬-070000034.html
https://tw.news.yahoo.com/新詐騙太兇-手機輸入-21-瞬間被接管-詐團兩天盜刷賣股得手366萬-070000034.html