SHEIN Order Cancelled but Refund Still Missing

I cancelled my Shein order yesterday in the United States and was charged 109 dollars in total for shirts, a mic/phone item and stickers. After cancelling, Shein only refunded 78 dollars to my account, so 31 dollars is still missing. I tried to contact Shein customer service about the missing part of my refund, but they did not respond and when I tried calling, the call was hung up. My order number is Gsu1ba65u00ngxm and the payment was made with my card ending in 3108. I request that Shein refunds the remaining 31 dollars as soon as possible to my card ending in 3108 and informs me clearly about the status of this refund.