报错内容：
Access to XMLHttpRequest at 'http://www.z........n.com/api/login'
from origin 'http://z........n.com' has been blocked by CORS policy:
The 'Access-Control-Allow-Origin' header contains multiple values
'*, http://z........n.com',
but only one is allowed.
意思是：
已被CORS策略阻止：“Access Control Allow Origin”标头包含多个值*
但只有一个是允许的。