Not blaming you, just unsure how this could have been missed on the checkout page.
Screenshot: https://imgur.com/a/zpfrp7u
First it says 10 licenses, then it highlights that the cost will be 200 per month. When you try to reduce number of licenses below 10 it will automatically switch you to Pro plan, voiding 10-license-minimum requirement.
Not sure what else they could have done?