If you are looking to troubleshoot any DirectTv devices then click here http://soc.att.com/2yEr2Y6. You should be able to find all the information needed or call the phone number on the top of your bill.
The issue and preferred resolution, in GetHuman814492's own words:
I just bought a Green Dot card from Walmart. I am trying to use it to buy something online and it won't let me. How do I resolve this?
I trust that Green Dot will make this right and come up with a resolution that is fair.
Help with my Green Dot issue
Follow this to see how it gets fixed
Find similar issues & what fixed it
Follow 3 or more issues like yours to increase the chances that another customer helps you find the right answer.