The Prophet ﷺ said, "Fruit is not to be sold for dates, nor is fruit to be sold until its ripeness becomes apparent."Then Zayd bin Thabit met Abdullah bin Umar and said, "The Messenger of Allah ﷺ granted a concession in the case of arāyā."Sufyan explained, "The arāyā were palm trees that used to be gifted to the poor. They could not afford to wait for the dates to ripen, so they would sell them for whatever fresh dates they wished."
حدثنا محمد بن يزيد أنبأنا سفيان بن حسين عن الزهري عن سالم
عن النبي ﷺ قال لا تباع ثمرة بتمرة ولا تباع ثمرة حتى يبدو صلاحها قال فلقي زيد بن ثابت عبد الله بن عمر فقال رخص رسول الله ﷺ في عرايا قال سفيان العرايا نخل كانت توهب للمساكين فلا يستطيعون أن ينتظروا بها فيبيعونها بما شاءوا من ثمره
Its chain of transmission is sahih. It has already appeared at 21507 and 21469.