Indeed Wiggy you are correct I regret to say.
The last FAA NOTAM was 25 July and prohibits flights below FL 260 except for operations to/from Kabul airport.
As “Ginger Ninja” said earlier, what happens in the event of an emergency?
I fear the FAA (and perhaps also United) are asleep at the switch here.
Surely a prudent operator would literally steer clear anyway, e.g. as recent BA tracks show?