Can't add new user to a repo even if he's added to my account

[Foodin]

So I have a free plan and have 5 users added to my account. I want to add one of them to two repos, but I can't. He's been added to only one, when I try to add him to the second repo, he gets the email invitation and when he clicks on it, it says the plan needs to be upgraded. Should't I be able to add users to multiple repos?? Please help!

[Foodin]

Solved! :)