How do I add money in my PSN card?

What will happen if i never add money to my walmart money card that has a negative balance?

• I have a prepaid walmart money card.The type that charges a $3.00 monthly fee. I used it on a cruise recently.It was loaded with $600.00 and I spent $319 on the cruise. I used the card eating out as well and when I last checked the balance it was around $36.00. A week later I went to walmart to do my grocery shopping. On a whim I had the cashier check my balance on the card and to my surprise she said it was $236.00. She printed out the balance for me (which I still have) and I then used the card to buy my groceries. My remaining balance after groceries was supposed to have been $67 so I spent another $27 later on amazon.com leaving my balance at $40, yet today when I tried to use the card it was declined. I went online and the balance said it was negative $130!! How can this be? What will happen if I never load more money to this card and have this high of a negative balance? I did'nt think prepaid cards could have negative balances except for fees.

• Answer:

  They send it to a collection agency. They don't forget about it.