担保支付调用预下单接口总是返回

{"err_no":2008,"err_tips":"签名校验异常，请使用正确的签名","data":null}

用IDE验签工具校验是一致没有问题的

传参：{"total_amount":900,"subject":"购买月度会员","sign":"aedf4a8e73680fa776c0e3ad72bda9e6","out_order_no":"uvbl2023041218194993600110983379","valid_time":7200,"body":"购买月度会员","app_id":"tt62fc1441fdc4f06b"}

抖音生成的小程序签名sign : aedf4a8e73680fa776c0e3ad72bda9e6

X-Tt-Logid: 2023041218194943472FD8C5D5A4326CFD