I can't input the number starting from "N" in the field of the phone number on the online application screen for "Omatome Seikyu Service (combined billing method)" or "Web Billing."
回答
The 10-digit number starting from "N" is the contract number for OCN service of NTT Communications.
You can't apply for "Omatome Seikyu Service (combined billing method)" or "Web Billing" with that number. Please apply with the 10-digit number starting from "0," "6," "7," "8."
The number is written in the section of "お客様電話番号等 (customer's phone numbers)" on the bills or in the section of "ご請求番号 (billing number)" of "ご請求額お知らせメール (billing amount notification email)" that is sent by NTT Communications monthly.
