The green active icon indicates that your phone number is free to transact with Boku i.e. your number has not been blocked or prevented from making payments with our service. If you want to block your number, follow the guidelines in our FAQ: I want to block my phone number to prevent future charges.
Note: even if your number is active with Boku, this does not mean that your network provider hasn't blocked your phone from making mobile payments. If you struggle to make payments with Boku, contact your network provider to ask whether there are any blocks on your account that are permitting you from transacting. You'll always want to verify with your network provider that the number is enabled for use with premium SMS and direct carrier billing services.