Since you posted in Gen 2 I assume you have one. Not aware of Gen 2 heating issues, but if you have a Gen 1 and posted in the wrong section then you should see the links in my signature.
If you have a Gen 2, get it to the dealer while it is under warranty.
Noticed the exact same thing recently. Got my Kinetic Blue Premier in May, so hadn't needed heat until recently. Even on HI, the only one where I was able to get heat, was on Max Defrost.
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