Megan Fox is engaged again, reports the new Us Weekly (on newsstands now).
On-again beau Brian Austin Green popped the question to Fox, 24, June 1.
But in all the excitement, the happy couple somehow lost the ring, sources tell Us Weekly.
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"I saw her jumping up and down," a witness tells Us Weekly of the beachside proposal at the Four Seasons Hualalai hotel on the Big Island in Hawaii. "Later, I saw a half dozen staff sifting through the sand."
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Alas, the 2-carat sparkler, which the pair picked out together from Excalibur jewelry store in Beverly Hills, remains MIA.
"Security and maintenance staff spent a couple of hours looking for it," another source tells Us Weekly. "No one found it."
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Green, 36, and Fox began dating in 2004 but called off their previous two-year engagement in February 2009.