I would be willing to bet the factory didn't get the butyl tape in place correctly somewhere on this window.
Get a roll of butyl tape and a tube of Proflex RV and remove the window.
Re-install with new tape and put a bead of proflex RV around the perimeter of the window frame. You will have a permanent fix.
Caulking the edge of the window frame will last for anywhere from 2 weeks to a year, but you will still have a leaky window.
Here is a picture of my front window with the butyl tape folded under at the top corner.
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John U