Abu Sa'id Al-Khudri (May Allah be pleased with him) reported:
Messenger of Allah (ﷺ) forbade turning the water-skin upside down and drinking directly from its mouth.[Al-Bukhari and Muslim]. (IT)
App reference (IT): Book 3, Hadith 35 (IT)
Arabic/English book reference (IT): Book 3, Hadith 762 (IT)