Why are the leaves of my Lycium barbarum tree all curly? What do you think of it? The leaves are not watery at all. ......

Maybe you have powdery mildew or starscream. If there is powdery mildew on the surface of leaves, it is powdery mildew. It can be treated with stone sulfur mixture. There are tiny red worms and filaments on the north back of leaves, that is, red spiders, which can be treated with mirex or cigarette butts: soaking in water to get juice and spraying leaves.