A man was praying. He did ruku’, sajdah and supplicate after tashahhud -

اَللَّهُمَّ إِنِّي أَسْأَلُكَ بِأَنَّ لَكَ الْحَمْدُ لَا إِلَهَ إِلَّا أَنْتَ الْمَنَّانُ بَدِيعُ السَّمَاوَاتِ وَالْأَرْضِ يَا ذَا الْجَلَالِ وَالْإِكْرَامِ يَا حَيُّ يَا قَيُّوْمُ

Allaahumma inni as'aluka bi-anna lakal-hamdu, laa ilaaha illaa antal-mannanu badi'us-samawaati wal-ardi, yaa dhal-jalaali wal-ikraam! Yaa hayyu yaa qayyum

O Allah, I ask Thee by virtue of the fact that praise is due to Thee, there is no deity but Thou, Who showest favour and beneficence, the Originator of the Heavens and the earth, O Lord of Majesty and Splendour, O Living One, O Eternal One. The Prophet (ﷺ) said: 'Do you know what he has supplicated with?' They said: "Allah (SWT) and His Messenger (ﷺ) know best."He said: 'By the One in Whose Hand is my soul, he called upon Allah by His greatest Name, which, if He is called by it, He responds, and if He is asked by it, He gives.'

Reference: Sahih (Albani). Abu Dawud: 1495