Pure earnings and accepted duas
إِنَّ اللَّهَ طَيِّبٌ لَا يَقْبَلُ إِلَّا طَيِّبًا
Inna-llaha tayyibun la yaqbalu illa tayyiba.
"Indeed Allah is pure and accepts only what is pure — and has commanded the believers what He has commanded the messengers."
Narrated by Abu Hurayrah. Sahih Muslim 1015 · Nawawi's Forty · #10
A short reflection
The hadith continues with a man raising his hands in prayer — fed by haram, clothed in haram — how could his dua be accepted? The income and the dua are connected.