Sandspinner mantle - incorrect Heart of Azerite levels

I’ve just got an ilvl 310 Sandspinner mantle, and the Heart of Azerite levels in game are level 11, 14 and 17, but in AMR they are 9, 12 and 15.

I’m an Affliction warlock.

BTW - I will be levelling up my necklace quite quickly, and gearing up in general, so no need for a fast response!