First of all I want to say that I don’t have full colection of March Of Lich King(thats important) and I bought Lich King mini set.
After I claim Lady Deathwisper from rewards track game propose me to change my usual card for another legendary, I accept it and get second Frostmourne instead if something that I don’t get. So maybe it’s bug and maybe not, idk, so just explain me this .