Help with new WaMU Chase debit card?

After activating it, I went to use it at wal-mart today and the card wouldn't work. I had to use something else to get my stuff.

My receipt reads " payment declined--reason no 5" What does that mean?

Now, if I remembered the correct PIN (99% sure I did) and I have plenty of money in the account the card's for...why didn't it work?

Does Wal-mart not accept MasterCard?
Oh...I tried the card 2x's: under Credit and then debit and both times their machine required I put in a PIN and I got the message above.
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~~I would take the card to your nearest branch. It could be a problem with the magnetic bar. If not, maybe you have the incorrect pin code, and a teller can help you set up another. They are open on Saturdays.~~
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Depending on the kind of account you have with Chase, you could have a preset spending limit per day. My roommate can not use more than $400 per day through ATM's or POS. Also, if he does not have at least $100 more than he is trying to check out on a POS, it will decline. If he is buying $200 worth of stuff, he has to have a balance at least $300 or it will deny. Definitely check with Chase, they will be the only ones who can answer it definitively.
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Walmart accepts all major cards.

On the back of your card is a customer service number.
Call that number and if you can't get a human being on the line immediately push either Zero, Star or Pound sign on your phone.
Usually one of those will send your call to a real life operator.
You will probably need to have your bank account number and/or PIN number ready to identify yourself.

Sorry... only your bank knows why it did not work.
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you should tried credit again and yes the POS terminal will ask you for a pin but there is usually another button that say ""Cancel" ) and the POS terminal screen will go to credit.
or you could ask the clerk how do I pay with credit they know the routine
and worst case most cashier can always enter the card number in manually as well
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Call your bank. They will be able to tell you the problem.

Of course Walmart takes Mastercard.