If you are like most of the others with a Hint subscription, it is not one made from an in-app purchase that is managed by Apple. In that case it makes no difference if you have the app or not and you most likely followed a link from an app or website advertisement that claimed to offer a free astrology reading on their website . In the fine print of that reading, it also said that the reading is a free trial and you will be signed up for a subscription. I agree it is a scam, but Apple has nothing to do with any subscription service started on a website. They are billing your card directly and it is not going through Apple.
If that sounds like what happened to you, then try to cancel here:
https://help.hint.app/hc/hint-help-center/articles/1722517688-how-do-i-cancel-my-subscription
Their refund policy is available here:
https://help.hint.app/hc/hint-help-center/articles/1722517666-refund-policy
Other help topics are available here:
https://help.hint.app/hc/hint-help-center/en
If you are unable get the subscription removed, you will need to dispute the charge with the credit card company. Make sure they block further charges as simply issuing you a new card with a different account number will not stop the subscription charges.