Questions about billing will need to be resolved by the Customer Support team and cannot be resolved on the Community Forums.
To contact the billing team, please submit a new support request from your Cloudflare account directly through the Cloudflare dashboard. Visit https://dash.cloudflare.com/?to=/:account/support and choose Billing. Please share your ticket number here so that we can track it.
It sounds like you subscribed to Pro Annually. You’d need to contact support either way to get help with this.