Megan Fox Lost Engagement Ring!

Screen bombshell Megan Fox is thisclose to becoming Mrs. Brian Austin Green.

Now if she could only find that pesky 2-carat engagement ring!

The ex-Transformers hottie is reportedly engaged — again — to wed longtime beau Brian Austin Green, but in a spat of bad luck that could only make the Devil chuckle, Megan’s already lost the ring.

Brian popped the question as the couple lounged proposed on the beach at the Four Seasons Hualalai Hotel in Hawaii over the Memorial Day Weekend. Megan happily accepted, but sometime during the bustle of excitement, the couple lost the ring on the beach, tipsters tell Us Weekly Magazine.

“I saw her jumping up and down,” an onlooker whispers. “Later, I saw a half dozen staff sifting through the sand.”

“Security and maintenance staff spent a couple of hours looking for it. No one found it,” another source adds.

Green, 36, and Fox, 24, initially announced their engagement in 2006, two years after meeting on the set of ABC’s Hope & Faith. They called off the engagement in February 2009.