无法完成支付，502 bad gateway

配置完成以后，在支付宝的页面输入沙箱的帐号密码后报错:
url:

https://cashier.alipaydev.com/standard/payment/cashier.htm?orderId=02254161110f9416b40000-2-2NN4213&bizIdentity=trade20001

报错信息：

502 Bad Gateway
The proxy server received an invalid response from an upstream server. Sorry for the inconvenience.
Please report this message and include the following information to us.
Thank you very much!

URL:    http://cashier.alipay.net/standard/payment/cashier.htm?orderId=02254161110f9416b40000-2-2NN4213&bizIdentity=trade20001
Server:    proxy-2-1-3.daily.alipay.net
Date:    2020/02/25 19:56:33
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