Definitely open a ticket with Support. It is still under warranty.
Presuming it was also tested with the an alternate high quality cable (though not necessarily a 240W rated one) it should still be able to charge albeit at a lower current rating.
While not common, a few power adapters have been bad from the factory and some have developed issues over time. Support will get you setup with a replacement. At least the power supply died and not the charging circuitry on the mainboard! 
