What am I being charged $0.99 for?

One possibility is a subscription: See instructions in If you want to cancel a subscription from Apple - Apple Support

Another possibility is iCloud storage that was upgraded from the free 5GB plan to a 50GB plan: Cancel upgraded iCloud storage by downgrading to the free 5GB plan. See instructions in: Downgrade or cancel your iCloud+ plan - Apple Support

If the above doesn't help, be aware that this is primarily a user-to-user support forum; other Apple users like you. We don't have access to information about charges to your account. See each of the steps in the following instructions. They include information on contacting Apple Support if the other steps don't help: If you see 'apple.com/bill' on your billing statement - Apple Support

or go to Subscriptions and Billing - Official Apple Support

Likely iCloud storage, but nobody on these boards can say for certain. Check it and your other subscriptions, or contact Apple Support as described in the Related Article above.

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