Use the following procedure to untwist a twisted lap/shoulder belt.
Position the latch plate as close as possible to the anchor point.
At about 6 to 12 inches (15 to 30 cm) above the latch plate, grab and twist the seat belt webbing 180 degrees to create a fold that begins immediately above the latch plate.
Slide the latch plate upward over the folded webbing. The folded webbing must enter the slot at the top of the latch plate.
Continue to slide the latch plate up until it clears the folded webbing and the seat belt is no longer twisted.