Contact the Consulate-General using the following number (86-23)6373-3585 or try going to the institution yourself at 37/F, Metropolitan Tower, No.68 Zourong Road, Central District, 400010. You can also apply for the Japanese e-Visa online following a quick and intuitive 3-step application process that requires no visits to the Embassy.
Visa to JapanJapan Electronic Travel Authorization