Checked my bank statement and shocked to realize the $300 annual card fee incurred in early March! I could have called the hotline but it was too much a hassle. Instead, I voiced out my request via their online chat system built within the HSBC app. Turn out it is quicker than I thought! I just made the request and indicated the card number (last 4 digits). Take about 15 minutes for them to complete the request. No other request for information is required.
Anyway, the online support still advised me to do it myself by quoting the instructions at the end of the conversation (in Chinese).