phone number for apple.com/bill

First, the process you describe does not sound anything at all like Apple does things. I am wondering if this was a scam. If it was, change your account password NOW. Apple does not use telemarketers charging you to connect to them. In fact, if your bank provided you with that number, your card may also have been compromised and you should check with the bank about issuing you with a new card. A statement on your bill should clearly relate to Apple as its origin and Apple does not use scamming telephone numbers.

If you see 'apple.com/bill' on your billing statement - Apple Support

Recognize and avoid social engineering schemes including phishing messages, phony support calls, and other scams - Recognize and avoid social engineering schemes including phishing messages, phony support calls, and other scams - Apple Support

Sounds like your card has been compromised. This is done by using it at a terminal that has a skimmer/shimmer installed to read your card details. This is common at gas stations where the scammer has the ability to install it overnight with little interruption, but of course can happen in any location. The scammers use descriptions of charges for well known companies so you are likely not to dispute the charge. The scam has nothing to do with Apple and the resolution to a fraudulent charge would need to be resolved by your bank, since they are the one that approved the transaction. You can find more details about this scam here:

https://discover.hubpages.com/money/Apple-iTunes-866-712-7753-Scam