Hazrat Abu Umama RAA has narrated that Rasool Allah ﷺ said that on the day of Qiyamah when the book of deeds would be given to people in their hands someone would notice that some of their good deeds are not recorded in their book of deeds. He will say to Allah Ta'alah that my such and such good deeds are not recorded in this book of deeds. He will get a reply that because he used to do Gheebat (backbiting) against people that is why his good deeds have been erased from his record.

From Ma'ariful Quran, Interpretation of Surah Al-Nahl, by Mufti Muhammad Shafi RE