Dua 66 When living among irreligious & worldly people, pray this dua to protect your faith:
(Surah Ash-Shu'ara (26), Verse 118)

فَٱفْتَحْ بَيْنِى وَبَيْنَهُمْ فَتْحًا وَنَجِّنِى وَمَن مَّعِىَ مِنَ ٱلْمُؤْمِنِينَ

Faftab bainee wa bai nahum fat hanw wa najjinee wa mam ma'iya minal mu'mineen.

So judge conclusively between me and them, and deliver me and the faithful who are with me.

(Surah Ash-Shu'ara (26), Verse 118)

Recite this dua in the Qunoot of Isha prayer.
When Prophet Nuh (AS) saw that people had turned away from Allah and there was no hope left for them to come to faith, he prayed to Allah to save himself and his few believing companions from Allah's punishment.
When forced to live among irreligious, materialistic, and ignorant people, or when compelled to spend life in such an environment, we should pray the above-mentioned dua to protect our faith and conviction, and to seek refuge from Allah's wrath.