GitHub: Load Repositories fails

when i configure a plan with GitHub repository Bamboo fails to load the repositories from GitHub with a particular user. I get the following error.
"No repositories found for user foobar."

I'm able to log into GitHub with this user account and access repositories.

Bamboo is able to succesfully clone the repository and execute the plan when i do the following:

• use another account X + pwd
• load repositories + select repository
• replace account X with account foobar + pwd
• save