s5 won't feed both lines of filament

[LHSEngineering 0]

The first filament loads fine the dual filament of any kind - PLA, breakaway, etc - always gets to the feeder before being transferred to the bowden tubes and stops. It's as if the gears inside the box aren't working. I have taken the box cover off, looked for any obstructions and can't find any. Please help. 

[UlrichC-DE 115]

I assume that you always cut the ends on the fimament with the supplied pliers.

Also that the lever of the feeder is closed. Or that the lever has a small but noticeable resistance when closing the lever.

Normally, the feeder of the printer takes over at this point. If it does not make contact with the filament, it will not work.

Just one idea

The bowden goes deep into the sensor at the back wall of the material station?

The Bowden goes there deeper than with the normal clamps.