Drone Flight Application?

Hi folks,

I’ve successfully registered my drone with the authorities, but need permission to fly in any kind of city area… the official website provides an email to contact but every time I do it fails. This is the email I’ve found. hqt-jcab.mujin@ml.mlit.go.jp

Does anyone know of any other ways to apply for permission to fly a drone in city areas? I have permission from the company who owns the land they want me to film but I cannot figure out how to submit the application…

Thank you!