I'm trying to cancel a .99 charge on my credit card every month

If the charge is for iCloud storage upgraded from the free 5GB plan to the 50GB plan: Cancel upgraded iCloud storage by downgrading to the free 5GB plan. See instructions in the following Apple article: Downgrade or cancel your iCloud+ plan - Apple Support

For subscriptions, there is an Apple article that explains how to cancel subscriptions. Click on the following link: If you want to cancel a subscription from Apple - Apple Support

Hello~ Take a look by clicking on the link below…

Subscriptions and Billing - Official Apple Support

Once inside the link you may click on other highlighted tabs of interest in order to view applicable information.

~Katana-San~

Did you follow the steps here: If you want to cancel a subscription from Apple - Apple Support

~Lyssa