K245 headphones: earpiece connectors come loose

I bought a pair of these in June 2022. In October, after light use at home, the two metal connecting rods between the right earpiece and the junction unit came loose and wouldn't stay in their slots. This means the earpiece stands proud of my head rather than snugly fitting as it should. Is this a common fault? The retailer, to whom I've returned them, refuses to help, telling me I've damaged them myself. This is a disappointing failure of an AKG product. Perhaps this fault can be repaired - any ideas?
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