There are two important steps to enabling an Amazon market on your Settings tab. First, add an Amazon account, and then add and enable an Amazon market.
Before you begin adding Amazon accounts, you'll need an Amazon Pro Merchant account. If you don't have a Pro Merchant account, please sign up for one with Amazon Services.
After you have created your Amazon Pro Merchant account on Amazon, you can add the account then enable a market in Monsoon Marketplace.