DIAGNOSIS The plastic latch mechanism on the back of the dust bin is broken or the metal catch on the stick is bent.
FIX Inspect the black plastic latch on the bin. Press it. The small metal hook should extend. If it's broken or missing, the bin needs replacement (part VCA-CB75A). If the latch seems okay, check the silver metal catch on the stick body. It should spring back when pressed. If it's bent, gently pry it back into position with pliers.
IF THAT DIDN'T WORK The internal spring in the bin's latch assembly is dislodged. This is not repairable. You must replace the bin.
HEADS UP Always press the bin release button before pulling the bin off. Yanking it off without pressing the button will snap the latch.