are you sure the pump is compatible with a threadless valve?

I believe it is but not 100% sure. Are there pumps made specifically for threadless valves?

Are you sure you have the chuck latch in the correct position?

Yes, it still works fine with the threaded valves.

I'm just surprised that after 3 months the parts would wear out. Does anyone else use their pump on both threaded and threadless valves without problems?