The Prohibition Of The Names Malik Al-Amlak Or Malik Al-Muluk "King Of Kings" Sahih Muslim 2143 b
Translation
Abu Huraira reported from Allah's Messenger (ﷺ) so many ahadith and one of them was this that Allah's Messenger (ﷺ) said
The most wretched person in the sight of Allah on the Day of Resurrection and the worst person and target of His wrath would of the person who is called Malik al-Amlak (the King of Kings) for there is no king but Allah.