All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
If the narration of the names of Allah is within a complete speech such as Tasbeeh (saying Subhaan Allaah, i.e. how Exalted Allah is), Tahmeed (saying Alhamdu Lillaah, i.e. praise be to Allah), or supplicating - such as saying, سبحان العظيم الرحيم الكريم المجيد
Subhaan al-‘Adheem, ar-Raheem, al-Kareem, al-Majeed (Glory be to the Great, the Merciful, The Munificent , the Glorious,
or الحمد لله القريب المجيد الحميد
Al-Hamdu Lillah al-Qareeb al-Majeed al-Hameed (Praise be to Allah, the Near, the Glorious, the Praiseworthy),
or ارحمني يا لطيف يا خبير يا ودود يا وهاب
Irhamni ya Lateef, ya khabeer, ya wadood, ya wahhaab
(Have mercy upon me, O the Gracious, O the Knower, O the Affectionate, O the Ever Endowing), then there is no prohibition in this, and there is no objection to it.
What is not legislated is worship by listing the names singly without complete speech, such as saying: Allah Allah, or the All – Hearing, the All-knowing, the Wise, or the like.
Sheikh Al-Islam Ibn Taymiyyah said in his Fatawa: “The Sharee’ah did not recommend from Dhikr (i.e., remembrance of Allah) except what was complete and useful speech, such as: لَا إلَهَ إلَّا اللَّهُ، (There is no God worthy of worship but Allah); اللَّهُ أَكْبَرُ Allah is the Greatest, سُبْحَانَ اللَّهِ وَالْحَمْدُ لِلَّهِ، Exalted is Allah and all praise is due to Allah لَا حَوْلَ وَلَا قُوَّةَ إلَّا بِاَللَّهِ There is neither might nor power except by Allah.
As for the singular noun, such as: Allah, Allah, or the pronoun such as: He, He – this is not prescribed in Quran or Sunnah, nor is it narrated from any of the righteous predecessors, nor from the well-known scholars of the nation whom people imitate; rather, misguided people from later generations stick with it.”
It should be mentioned that the Names of Allah are not limited to a specific number; Ibn Taymiyyah said in Dar' Ta'arud al-'Aql wan-Naql: “The correct view of the majority of scholars is that the saying of the Prophet : “Verily, Allah has ninety-nine names; whoever memorizes them all will enter Paradise.”; means that whoever memorizes the ninety-nine names of Allah will enter Paradise, but this does not mean that he has only ninety-nine names, because in the other Hadith narrated by Ahmad and Abu Hatim in his Saheeh “I ask You by every Name belonging to You which You have named Yourself with, revealed in Your Book, taught to any of Your Creation, or preserved in the knowledge of the Unseen with You...”
Allah knows best.