The Messenger of Allah ﷺ forbade letting one's garment hang loose during prayer.
حدثنا هناد حدثنا قبيصة عن حماد بن سلمة عن عسل بن سفيان عن عطاء بن أبي رباح
نهى رسول الله ﷺ عن السدل في الصلاة
No references are available.
[Its chain of transmission is daif]. Abu Dawud also narrated it, in the Book of Prayer, Chapter on Draping the Garment During Prayer, no. 643, as a suspended report, and Darimi, no. 1386, from the hadith of Asal by this route. Asal is daif (Taqrib). There is another route for it, extremely daif, found in Abu Dawud, no. 643, containing a mudallis narrator transmitting from liars and using the ambiguous form "an", and it has corroborating reports, all of them daif.On this subject there is also a report from Abu Juhayfa [Tabarani in Saghir: 2/38 and Awsat: 7/95, 96, no. 6160, containing Hafs bin Abu Dawud, who is discarded (matruk)].