what is the .99 I pay each month for?

See your purchase history in the iTunes Store on a Mac or PC - http://support.apple.com/HT204088

iTunes Store charges on credit and debit card statements - https://support.apple.com/HT201382 - "See an unfamiliar iTunes Store or App Store charge? Before you contact Apple, check your iTunes Store purchase history for more details."

If you think there really is something that shouldn't be there:

Report a Problem - http://reportaproblem.apple.com - "Sign In for help with iTunes purchases made in the last 90 days"

Other ways to contact iTunes Store Support:

https://support.apple.com/contact

https://www.apple.com/emea/support/itunes/contact.html

No way for us to know. As this is a user to user forum and we are users like yourself we have no insight into your charges. You should know what you are paying for though. As recurring payments require several steps before being activated.

$.99 cents is normally an iCloud Storage charge. The 50GB option to be precise.

iCloud storage plans and pricing - Apple Support

You can manage it in Manage your iCloud storage - Apple Support and see if you are in fact paying for iCloud.

Otherwise, check your subscriptions for any apps you may have initiated a recurring subscription for one:

View, change, or cancel your subscriptions - Apple Support

Look at your purchase history and see.

Could be iCloud storage

Send your Mac/iPhone to me. I'll look and send it back to you.