Sunan Ibn Majah
1691
Sahih+3

It was narrated from Abu Hurairah that the Messenger of Allah (ﷺ) said:“When anyone of you is fasting, let him not utter evil or ignorant speech. If anyone speaks to him in an ignorant manner, let him say: ‘I am fasting.’”

SahihAl-Albani
SahihMuhammad Fouad Abd al-Baqi