They consider it a favor to you that they have accepted Islam. Say, "Do not consider your Islam a favor to me. Rather, Allah has conferred favor upon you that He has guided you to the faith, if you should be truthful."
The Saheeh International Quran Translation
يَمُنُّونَ عَلَيْكَ أَنْ أَسْلَمُوا۟ قُل لَّا تَمُنُّوا۟ عَلَىَّ إِسْلَٰمَكُم بَلِ ٱللَّهُ يَمُنُّ عَلَيْكُمْ أَنْ هَدَىٰكُمْ لِلْإِيمَٰنِ إِن كُنتُمْ صَٰدِقِينَThey consider it a favor to you that they have accepted Islam. Say, "Do not consider your Islam a favor to me. Rather, Allah has conferred favor upon you that He has guided you to the faith, if you should be truthful."