´It was narrated from Muhammad bin Jubir bin Mutim that his father:` "I lost a camel of mine, so I went to look for it in Arafat on the day of Arafat. I saw the Prophet standing there and said: 'what is he doing here?' He is one of the Hums.'"
Explanation & Benefits
Hafiz Muhammad Ameen
(1) They said this based on the same custom of ignorance (jahiliyyah) which was mentioned in the previous hadith. They were likely unaware of the new ruling.
(2) It should be noted that these two hadiths and the forthcoming hadiths have no direct connection with the aforementioned chapter; however, from them, the obligation (wujub) of standing (wuquf) in Arafat is established. It appears that these hadiths were under a separate chapter which was omitted during writing.
Source: Sunan Nasa'i: Translation and Benefits by Shaykh Hafiz Muhammad Amin Hafizullah, Page: 3016