What is the ruling on money earned from selling fertilizers in excess of the farmers' needs to traders and companies at a price higher than the cooperative's official price, with their consent, and what should we do if this money is unlawful, knowing that it is unknown and has been spent, with only a car remaining that the questioner benefited from?

Your taking of the extra money is a transgression against trustworthiness (amanah). You must return what you took to the association. If you do not know the exact amount, then you must return what clears your conscience, unless the authorized party in the association permits it.

The merchant's knowledge of the excess does not make it permissible, for the excess is not yours but belongs to the entity that authorized you to sell, based on the hadith of Urwah ibn al-Ja'd al-Bariqi.

And the misfortunes that have befallen you might be due to the unlawful money you acquired. Therefore, you must free yourself from it by returning it to its rightful owner. You are accountable for the amount of money you took, but what you bought with it remains your property.