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]. (DE)
App reference (DE): Book 3, Hadith 35 (DE)
Arabic/English book reference (DE): Book 3, Hadith 762 (DE)