I use CR60 on windscreen. Initially I have same problem. But once i tried many method and i found out the most effective way to pass through.

1. The smart Tag must attached at the centre of the windscreen and just right above the dashboard and away from your seating position.

2. You have to drive really slow ~10+km/h to let the smart tag work. It works on every smart tag toll i went through with this method.

***The key point ---> Attached on right location + Don't rush.