I cannot create more than 2 private repos.
You are using a Legacy Plan
Your current plan is part of our legacy per repository billing subscription. These plans have been removed in favor of per user billing. Your current plan will remain in effect unless changed by you.
However, the UI Slider (which is IMO a really bad UX experience only allows a minimum of 6 users, so you have to pay to upgrade, just to downgrade, which is ANOTHER bad UX experience…)
<div class="ui range" id="seats-range" data-min=" 6 " data-max="151" data-start="6"> ... </div>