If so this is probably under warranty.
If it is not a quick fix with a little Allen wrench I would contact the Moen Customer Care line. From their site:
Call: 1-800-Buy-Moen (1-800-289-6636)
8:00 am to 8:00 pm EST Monday thru Friday
9:00 am to 5:30 pm EST Saturday
Closed on Sundays and all nationally observed holidays
From the reviews on their own site it appears that the loose handle has been an issue but they have sent replacements.
Let us know the company's response so we can let the world know.
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