Google Developer Console 的凭证方权限

I got an problem after i create and APIs on Google Developer Console and enable the GCM service, but i want to add an server key at Credential next to APIs on left hand menu. But it show me You do not have sufficient permissions to view this page. Below are the image:

这是我需要添加的配置吗？ 我确实遵循了什么您没有足够的权限查看此页面 https://stackoverflow.com/questions/31869154/you-do-not-have-sufficient-permissions-to-view-this-page清除缓存并使用隐身模式登录，但仍然不起作用。

EDIT有时我重新登录它会恢复正常，当我单击另一侧并单击返回时，它会再次显示错误，我的解决方案是转到凭据而不是使用右上角的帐户注销并重新登录，让它将您重定向回凭据，比它有效。那么有没有什么办法可以永久修复而不需要重新登录呢？

Thanks

It because of you have logged in multiple devices. so u have to log out from all devices. to do this go to gmail.com and log in using your email and password. and scroll down . you can see Details link . Click that link.

it will open new window. there u click

注销所有其他网络会话。比清晰的历史。比登录并尝试。它将打开而不显示错误。