What is the 10-digit number starting from "00" or "01" printed on paper bills (notification of bank account deduction, etc.) as "Okyakusama Denwa Bango tou (or customer billing number)"?
回答
The numbers starting from "00" or "01" are your own 10-digit billing number for the charge for FLET'S services of NTT EAST / NTT WEST, or Hikari Denwa (Hikari phones) or your own 10-digit number for the charge for OCN / phone services of NTT Communications.
The numbers starting from "00" from NTT EAST / NTT WEST are printed on the "starting guide" of FLET'S services or Hikari phones.