Hadith #789 (Jami' al-Tirmidhi)
Book: The Book on Fasting
Narrator(s): Aisha bint Abi Bakr, Ayoub bin Waqd al-Kwfy أيوب بن واقد الكوفي, Bashr bin Mua'dh al-Qdy بشر بن معاذ العقدي, Hisham bin 'Urwa هشام بن عروة, Urwa ibn al-Zubayr عروة بن الزبير

The Messenger of Allah said: “Whoever stays with a people, then he is not to fast without their permission.”

Source: https://parallelquran.com/hadith/jami-al-tirmidhi-789/