﴿ وَمَآ أَسْـَٔلُكُمْ عَلَيْهِ مِنْ أَجْرٍ ۖ إِنْ أَجْرِىَ إِلَّا عَلَىٰ رَبِّ ٱلْعَٰلَمِينَ ﴾

““And no reward whatever do I ask of you for it: my reward rests with none but the Sustainer of all the worlds.”

Please check ayah 26:135 for complete tafsir.