微信支付报错：支付验证签名失败

调起微信支付报错“支付验证签名失败”，参考代码如下：

let payInfo = await this.payModel.getCreatePay(this.selectedCard)

ToastUtils.showToast("调起微信支付")

let req = new wxOpenSdk.PayReq()
req.partnerId = payInfo.partner_id
req.appId = APP_ID
req.packageValue = 'Sign=WXPay'
req.prepayId = payInfo.prepay_id
req.nonceStr = payInfo.nonce_str
req.timeStamp = payInfo.timestamp
req.sign = payInfo.sign

let finished = await this.wxApi.sendReq(getContext(this) as common.UIAbilityContext, req)