The first thing to do is log into your reseller portal by going to resellerportal.reachmail.net. On the Dashboard you will see the ReachMail accounts that you're reselling. To edit the monthly allowed volume for a specific account simply click on the Edit Settings icon.
The next page that will open up is the Account Setp page for that specific account. This is where you can view the Account Name, Account Key, Company Name, Email Address, and Max Monthly Volume. Additionally you can set a Max Monthly Volume by changing the value in the box next to the label. If you have a default monthly volume set in your settings it will be automatically populated here.
For help setting a default monthly volume for new accounts to inherit, click here.