The billing on iOS is handled by Apple. Apple will send you a receipt of your subscription via e-mail. Often it can take 3-5 days to arrive. In case you have e-mail notifications turned off, you can get your receipt by following the steps:
- Open the App Store.
- Tap your profile icon.
- Tap your name at the top of the profile page.
- Scroll down and choose Purchase History.
- Find the order and tap the “Total Billed” label to see the transaction details.
- Tap Resend to have it emailed to you again.