Good afternoon! Great pictures. I don't know, but I am sure others will. A few questions to help with the diagnosis. Did the flowers bloom on a stem from the top of the cane or from all along the length of the cane? Rub the underside of the leaves with a white paper towel. Do you see rust or red? How much/what kind of light is the plant receiving? How often do you water and how dry do you let the plant get? Do you fertilize and if so how often and with what? Have you ever repotted the plant?
The older canes on my noid den. phals' shed their leaves. I have old canes with only one leaf at the tip. However, I am concerned to hear the new cane has lost it's leaves too. Joe