Trouble using Groupon

I just became a member of Groupon and went to use my first Groupon last night at NYC Restaurant called Choice which was featured in your e-blast. Not only did I have trouble using your coupon but they tried to act like they had no idea what I was talking about. Do these restaurants know when your going to use them?? Is that normal?? The communication between your company and the restaurant was unbelievable - thats the whole point of signing up for your company is to go to these places!!! I believe in second chances so I haven't told everyone to unsubscribe yet but I hope the next place you lead me to doesn't end in embarrassment.