2011 4Runner - lift gate water leak or drain? around window

Hi- I have a 2001 4Runner…I recently removed one of the handles used to close the liftgate (there are two-one on the right, one on the left) located on the bottom of the liftgate. When I did, after recent rain, I noticed lots of water inside the lift gate. I looked inside with a flash light and saw it was all very wet! I know there are drain holes in the lift gate, but…this seems like a problem. the water clearly is entering along the right or left edge of the rear lift gate window… Is this normal? appreciate comments or knowledgable feedback!