My Mom has so Far Been RIPPED OFF by McDonald's ***RESOLVED*

my mom so far is out $30.00 because when she reloaded her arch card on Saturday Morning January 12th, 2013 the employee either accidentally or maliciously made an operator error and it did not register the $30.00 balance but instead stated my mom had used up the balance in purchases, MY MOM DID NOT CHECK HER RECEIPT ON THE 12th of Jan., my mom is old and goes there every Saturday AM for a breakfast sandwich, when she returned a week later(following Sat.) and tried to use her arch card, she had no positive balance.. my mom is partially to blame for not checking the receipt, but there are new employees almost daily (high turnover) and it makes you wonder about the motives about the employee who pulled this stunt on my mom.. if mom would have caught the mistake, I'm sure the grunt would of said, "oh, I'm sorry my mistake".. I am trying like hell to contact the owner of that particular McDonald's a Mr. Blumenstock but can't get nothing but an answering machine.. this makes me sick ..I never trust a McDonalds worker