Sorry to tell you guy, but the proof is in the pudding. Your girlfriend should have checked her playslip and her lotto tickets after she made her purchase. Malfunctions do happen. You cannot sue the Texas Lottery because you do not have any recourse. Otherwise every one that made a similar claim would be suing their state lotteries for the same malfunction.
Next time buy your own tickets, don't trust others to know how the game is played and what is expected if you are a winner. You should always make sure that you are playing your lotto game, verify your numbers on yourplay slip, and make sure that you get a reciept before leaving the store where you play. Your girlfriend is not responsible for your ticket either. Why didn't she check the numbers and the ticket before leaving the store?
Good luck

