i have a 2016 mustang convertible, my passenger front widow keeps going up and down

my passenger side window goes up and down about 2 inches over and whileim driving .i have to pull over shut off the car to get it to stop.it hasbeen back to ford 8 times and they never fix it ..i bought it used from a dealer so it cant be a lemon law car im told.Any idea's onhow to fix this problem ...thanks Danielle.