Complaint Review: Bluebird Amex Pepaid Credit Card

After adding $250 to my card at Walmart, the same amount was transferred from my card by a Walmart service within a few hours without my authorization to a person that I do not know.  When texted by the "fraud dept." at Bluebird the same day, I replied "no" to their query as to whether it was me making the request.  I have never given my card or my account information or password to anyone.  After lodging a complaint with Bluebird, the company "denied" my dispute, saying that the " transaction(s) in question was authorized." 

NOTE:  The unauthorized transaction was never pending on my account for very long if at all, and the money was disbursed in less than 24 hours despite my "no."