Payment method for prepaid plan $150/180 days.

A Prepaid plan can be renewed one of two ways.

1. Renew plan from account balance.
   This option require you to choose from the $10, $25, $50, $100 pre-sets. The remaining balance not used to renew your $150 plan can be used to make long distance calls, use additional minutes, messaging, or data not included in your plan as pay-per-use. 
   
   
2. Renew plan from credit card.
   This option will directly renew your plan, for the exact cost of your plan, in your case $150. You will receive the exact minutes, messages, and data included in the plan. With this option, your account balance will remain at $0, and Pay-Per-Use features such as long distance, additional minutes, messages, data will not work since there is no balance to charge.

Which option should you pick?
Each of these options have their uses cases. A hybrid option is best for the most flexibility. For example If you choose the $150 plan auto-renew from my credit card, and a $10 auto top-up from my credit card. You can now make long distance calls to the USA at $0.60/minute (for a total of 16 minutes/month).

How to setup automatic plan renewal from credit card (without top-ups)

1. Login to your self-serve account.
2. Manage Prepaid
3. Change plan & add-ons
4. Select your phone type
5. Check "Auto renew upon expiration"
6. Click "from credit card"
7. Confirm

Bonus: Make sure your automatic top-ups is disabled to avoid being charged a top-up & your plan cost.

1. Account Overview
2. Automatic Top-Up
3. And if you see this, your all set. Otherwise select the option to cancel the top-up.

I hope that helps 🙂