This is a feature. You can try to disable caching for logged in users, but if it is in the main nav this still won’t help as according to the settings screen:
Don’t cache pages for logged in users
Unauthenticated users may view a
cached version of the last authenticated user’s view of a given page.
Disabling this option is not recommended.
There are also some other questions for that issue that might clear this up further: