This can happen if you are having trouble reaching the Xbox Live backend from your console. A few users who have had this issue have reported a profile restore on the system has solved it.
- Go to Settings, and then select Account.
- Select Remove Accounts.
- Select the gamertag that you want to delete.
- Select Delete.
- Select the following
- Select Delete Profile Only. This deletes the profile but leaves saved games and achievements. (DO NOT SELECT THE OTHER OPTION TO DELETE SAVED GAMES AND ACHIEVEMENTS)
At this point, re-add the profile to the Xbox.
- Home button > far left to sign in and/or choose profile
- Choose Add New
- Login to account