Hello,
Thank you for contacting the support and sorry for the confusion.
Rank Math PRO (all license types) comes with a FREE 15-day Content AI Trial. This is mentioned on the pricing page as well:

We also send out an email reminder three (3) days before the actual charge so that users can cancel the trial. We also mentioned this in our FAQs.
You can cancel the Trial at any time using this link:
https://rankmath.com/my-account/subscriptions/?tab=cai-subscription
→ Here is a guide on how to cancel your Content AI Trial
With that being said, we have initiated a refund on your Content AI subscription as requested. You should see a credit for the refund appear on your credit card statement anytime between now and the next 5 to 7 business days.
If you used a debit card for the payment, the refund might take up to 30 days to appear on your statement. Please note that refunds for international transactions can take up to 10 days to appear for credit cards or up to 60 days for debit cards.
For PayPal, it’s always almost instant.
We are continuously improving our products, so we request you to check back to see if we might have something relevant to your needs.
We would much appreciate any feedback you have to offer.