Telecheck Left Wal Mart empty-handed, but Telecheck called months later to collect debt Internet

I went Christmas shopping in Wal-mart several times last December. I remember now, there was one occasion when I left my check card at home and attempted to use my Wal-mart credit card. After that attempt failed I ran out to my vehicle for my checkbook...another failed attempt to pay for my selected items. Ultimately, I left the store empty handed with the intention of coming back at a later time to make the same selections.  So a little over a month later, I receive a call from a company claiming to collect a debt for Wal-mart. This call woke me up from a sound sleep, caught me off guard, and after being told that if I attempted to go into Wal-mart to make a purchase my sale would be declined, like an idiot I gave them my check card number so we could move forward. I paid the balance off plus a thirty dollar NSF fee.  After waking up, I had second thoughts about the decision I made to give the information and thought I'd better notify Wal-mart and my bank.  I also looked online in my checking account around the time this purchase was supposed to have occurred and I had over a thousand dollars in my account, so no way my check would have bounced.  Of course now, almost 2 weeks later, I realize the "purchase" they were referring to never occurred.  I paid $131.16 to be embarrassed in their store and walk out empty-handed. Needless to say, I'm not a happy customer!