Franco is well known for his generosity, but he will ask for no less valuable resources in return. Talk to him to see all his orders, maybe some of them you can already exchange for coins and experience. If you are particularly lucky, he can also offer crystals and fertilizers as a reward!
Select the order you need and tap the "Give" button to receive the reward.
If you don't like his offer, you can replace it by tapping the red icon with urn next to the "Give" button.