You already know that you are only talking to fellow users on here, that these are user-to-user forums, and not iTunes Support nor Apple - you shouldn't post personal info such as phone numbers on any public forum, I've asked the hosts to remove it.
Where have you seen this 'bill' ? If an email you are sure that it's a genuine email from Apple, not a phishing email trying to get your account and payment details ?
Phishing emails : Identifying fraudulent "phishing" email - Apple Support
Genuine iTunes emails : Identifying legitimate emails from the iTunes Store - Apple Support
Have you tried looking at your accounts purchase histories (including family members if you are a family organiser in family sharing) : See your purchase history in the iTunes Store on a Mac or PC - Apple Support ?