Now click on Upgrade button to add more users in your existing plan.
After Clicking on the Upgrade button it redirects to the miniOrange console enter the credentials and login
with the same id from which you purchased the premium plugin. And Select how many users you want to add
and fill all the other credentials.
After entering your card details click on Pay Now option.
After successful payment, you can add more users to your site as per the selected plan.