From Sahih Bukhari (Hadith 3766):
Narrated Humran bin Aban:Muawiya said (to the people), "You offer a prayer which we, who were the companions of the Prophet (ﷺ) never saw the Prophet (ﷺ) offering, and he forbade its offering," i.e. the two rak`at after the compulsory `Asr prayer
Reference: Bukhari 3766