From Sahih Bukhari (Hadith 5562):
Narrated Jundab bin Sufyan Al-Bajali:I witnessed the Prophet (ﷺ) on the Day of Nahr. He said, "Whoever slaughtered the sacrifice before offering the `Id prayer, should slaughter another sacrifice in its place; and whoever has not slaughtered their sacrifice yet, should slaughter now
Reference: Bukhari 5562