I'm telling you again - your conditions in events 2 and 3 are the same! It means that when you do the hold gesture over L1, both events are triggered.
And also, why did you put dt*-1 in lerp? Your sprite will move in the opposite direction! The third parameter in lerp function here is the speed. "dt" is the duration of one tick, if you want your sprite to move slower, change it to dt*0.5, or dt*0.1, but don't use zero or negative values!
It looks like you are changing things randomly hoping it will start working miraculously. Don't do this. Remove everything else except event #1 from your code, set SCROLL_Y variable to 1000 and see how it works. And then move from there.