google your union and go to contacts and they'll get you in contact with somone. If they try to connect you to your local rep in charge of your area ask for someone else. It's up to you if you explain why.
It is required that contact names and numbers should be posted in the break room and other locations with in the store. Look for a small to medium poster that has UFCW _____ on it with several lines on it. The lines should have the store stewards and the Union rep for your store, with contact information.
I wondered for a long time about that empty UFCW board on the break room wall. Then when contract negotiations began it suddenly got decorated. Now it is back to business as usual, I guess.