Contract Apple music

After signup, you would have received a confirmation email with the subscription details. This would list the duration of the trial period, and the due day for the first payment after that trial period, if you didn’t cancel before that time.

If you received an invoice for Apple Music before that time, then check your subscription settings. That will also list the current status and the due day for the next subscription fee payment.

View, change, or cancel your subscriptions - Apple Support

There might be an authorization hold, to check your payment method for validity of online subscription payments. That would not be an invoice, though. After that hold clears, the charge will be undone/reversed.

You may want to check if the invoice is really from Apple.

Identify legitimate emails from the App Store or iTunes Store - Apple Support

Avoid phishing emails, fake 'virus' alerts, phony support calls, and other scams - Apple Support

If you are convinced that an error has been made on Apple’s part, then contact the iTunes Support staff.

iTunes [Store] Support - Use this form for assistance with account and billing, code redemption, or purchase questions - https://www.apple.com/emea/support/itunes/contact.html

Worldwide iTunes support - https://support.apple.com/country-selector/itunes