The Prophet ﷺ said: Supplication (du'a') is itself the worship. (He then recited:) "And your Lord said: Call on Me, I will answer you" (xI.60).

عَنِ النَّبِيِّ ﷺ قَالَ الدُّعَاءُ هُوَ الْعِبَادَةُ { قَالَ رَبُّكُمُ ادْعُونِي أَسْتَجِبْ لَكُمْ }