The reason why Mao Chenyue from Fuguo Bank was not allowed to leave China by border controls is probably related to using trade financing to help some Chinese companies and entrepreneurs launder money and transfer assets overseas on a large scale. Transferring funds overseas, small and medium-sized enterprises go through exchanges, digital currencies, etc., while large-scale enterprises mainly go global through trade. This can also explain to some extent the reason why China's huge trade surplus and foreign exchange reserves have not increased correspondingly.