You have a subscription with the company directly so it is not managed by Apple where it can be cancelled easily. Most likely you got to the website through a post from a Social Media site where the poster was paid for the referral or through a website advertisement. It is an astrology site that claims to give you a free reading, which is actually a free trial subscription that you will be continually charged if you do not cancel. It makes no difference if you have the app or not as the subscription was most likely made through the website. Here is what that company offers for cancelling the subscription.
https://hint.app/en/help/cancel-my-subscription
If you are unable to cancel by contacting them directly, then you will need to dispute the charge through your credit card.