该错误消息说：

预计：aaa@xxx.com';实际：bbb@xxx.com

Expected: 'aaa@xxx.com'; Actual: 'bbb@xxx.com'

这表明一个userid参数被传递给acquireToken。这将导致在登录页面输入用户名字段设置为prefilled。但是，错误是说，当用户签署了他们改变了用户名字段给不同的用户。因为你问一个特定的用户，但没有得到该用户的令牌，acquireToken返回一个错误。看到这个答案的更多详细信息：

That indicates that a userId parameter is being passed to acquireToken. That would cause the username field in the sign-in page to be prefilled. However, the error is saying that when the user signed in they changed the username field to a different user. Because you asked for a specific user but did not get a token for that user, acquireToken returns an error. See this answer for more detail:

ADAL iOS的 - 不同的用户进行身份验证。预计userA@mydomain.com，实际userB@mydomain.com