While Matthew 18: 15 - 17 applies to sin of a serious nature, in the spirit of the principle stated in verse 15, we should kindly approach the offender privately and try to restore a peaceful relationship with him.
فَيَنْبَغِي أَنْ نَتَحَدَّثَ مَعَ ٱلْمُسِيءِ بِلُطْفٍ وَعَلَى ٱنْفِرَادٍ لِرَدِّ ٱلْعَلَاقَةِ ٱلسِّلْمِيَّةِ بِهِ .‏