Nepenthes albomarginata "merapi" not pitchering

[Spooky1]

I also have one referred to as "sambas" (Brown Spotted Red Pitchers) that is pitchering so I don't understand why the "merapi" (Green Pitchers) isn't. They both receive the same humidity, 69 - 86, and temperature, 69 - 82. When a new leaf grows out the small undeveloped pitcher hardens off and that is the end of it.

 

[tzestan]

I have a few albomarginata in same growing area.
One of them (kuching spotted) has not been pitchering for half a year now after transitioning to vining stage. Others like penang red and speckled are doing fine, but these are still in rossette. Not sure whether it is due to growth transition. Are your non-pitchering plant in transitioning to vining?

 

[Spooky1]

One of the more recent leaf tendrils has looped between the leaf and pitcher, is this an indication that it needs to climb?

 

[Tony Paroubek]

Photo's would be good...

How long have you had this plant? How big is it? How much light does it get etc etc..