It was narrated from Abu Sa'eed that the Messenger of Allah (ﷺ) said:
"When you have paid in advance for something, do not exchange it for something else." (Da'if)Another chain with similar wording. (DE)
English reference (DE): Vol. 3, Book 12, Hadith 2283 (DE)
Arabic reference (DE): Book 12, Hadith 2370 (DE)