CHICAGO (CBS) — If you wear your mask, you might be doing more than just fighting the coronavirus pandemic.

You could get a free sandwich.

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Manny’s Cafeteria & Delicatessen, 1141 S. Jefferson St., set a challenge on Twitter on Sunday. If the restaurant does not have to ask anyone to put a mask on properly for 30 days, then they will give out free sandwiches for a day.

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So far, it is not going well. Manny’s tweeted that seven people had to be reminded to wear their masks properly just Monday.

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But they are giving the challenge just one more chance.

CBS 2 Chicago Staff