Digital Paging Ripped me off by $40 for a $10 sim card Pasadena, California

I bought a pre-paid sim card for $51.50 From Digital Paging. Called to activate the card and found out that I only had the starter minutes and nothing extra. Went back Digital Paging two hours later and was told that I used up all of the minutes I paid for. Scrolled through my phone and noticed that I used a total of 32 mins.which is about $7.00 worth of minutes.Called O2 wirelsess and the rep said that I only had the starter minutes that come with every sim card sold and nothing more.Went to Best Buy and saw that the sim cards come in a hard plastic case,which mine did not and come with starter minutes for $9.99. You have to buy a card that you scratch off for $10,20,or 40.00 for additonal minutes.I went back to collect a refund and was refused.Digital Paging has a sign in the back of the counter in the corner on the register it says no refunds or exchanges. It is not posted on the counters or in plain sight or on the recipt.I just want my $40.00 back.