Client error: `POST https://api.mch.weixin.qq.com/v3/pay/transactions/jsapi` resulted in a `401 Unauthorized` response:

{"code":"SIGN_ERROR","detail":{"detail":{"issue":"sign not match"},"field":"signature","location":"authorization","sign_ (truncated...)

不是说SDK自动封装了签名了吗？我现在需要怎么操作？