Hometown Buffet sold Gift Card but do not accept it Nationwide

I bought Hometwon Buffet gift card.  But when I try to use it, none of their restaurants accept them. 

I called the phone number at the back of the card to verify balance.  The balance is verified $10 available and there is no acctivity.  Still Hometown Buffet restaurants do not accept it when I try to pay for my meal.

Then, I called Hometown Buffet customer service.  They told me they would report the issue to "district" and someone will contact me within one day.  But no one contacts me.  I'm calling everyday.  Every time, I'm told they will send a report and someone will contact me.  They won't give me phone number or email address to contact the party that solve the problem.

Basically, after one week daily calling, I still have this $10 perfectly good gift card that their system says good/valid and their restaurants won't accept.  They took my money to sell the gift card to me, but will not accept it.