Recite this adhkar upon unexpected awakening at night
عن عُبَادَةُ بْنُ الصَّامِتِ، عَنِ النَّبِيِّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ قَالَ: ( مَنْ تَعَارَّ مِنَ اللَّيْلِ، فَقَالَ: لاَ إِلَهَ إِلَّا اللَّهُ وَحْدَهُ لاَ شَرِيكَ لَهُ، لَهُ المُلْكُ وَلَهُ الحَمْدُ، وَهُوَ عَلَى كُلِّ شَيْءٍ قَدِيرٌ، الحَمْدُ لِلَّهِ، وَسُبْحَانَ اللَّهِ، وَلاَ إِلَهَ إِلَّا اللَّهُ، وَاللَّهُ أَكْبَرُ، وَلاَ حَوْلَ وَلاَ قُوَّةَ إِلَّا بِاللَّهِ، ثُمَّ قَالَ: اللَّهُمَّ اغْفِرْ لِي، أَوْ دَعَا، اسْتُجِيبَ لَهُ، فَإِنْ تَوَضَّأَ وَصَلَّى قُبِلَتْ صَلاَتُهُ ) رواه البخاري (1154).
“Whoever wakes up at night and says: ‘There is no one worthy of worship except Allah, alone, without any partner. To Him belongs the dominion, and to Him is the praise, and He is over all things competent. Praise be to Allah, and glory be to Allah, and there is no deity except Allah, and Allah is the greatest. There is no power nor strength except with Allah.’ Then he supplicates or asks for something, his supplication will be answered. If he performs ablution and prays, his prayer will be accepted.”