iTunes charge
I am currently enrolled in the 3 month free trial for apple music. I downloaded an album, and have been charged for it.
How do I get that charge refunded?
iPhone 6s, iOS 11.2.6
Realize it is also possible to purchase music from Apple while using Apple Music. I suspect that is what you did.
Apple's terms of purchase in the USA are, "All Transactions are final" (https://www.apple.com/legal/internet-services/itunes/us/terms.html), but some countries have different laws so check terms for your country at: http://www.apple.com/legal/internet-services/itunes/. If sales are final then it is Apple's decision if they want to grant a refund. You can always ask, and people do get refunds on a case by case basis, but Apple can also say no.
Get help with an item purchased from the App Store, iTunes Store, or iBooks Store - https://support.apple.com/HT204084
Report a Problem - http://reportaproblem.apple.com - "Sign In for help with iTunes purchases made in the last 90 days"
If a reporting a problem request is unsuccessful you can also try:
Other ways to contact iTunes Support:
https://www.apple.com/emea/support/itunes/contact.html
https://support.apple.com/country-selector/itunes
Apple Music: How to Purchase A Song After Streaming in Apple Music