How to unsubscribe from an App

Hi,

So I've downloaded an app called Nebula Horoscope from the App Store, and as I received their message about a discount for some astrological report it redirected me to a link where I've purchased that for $9.99, and it told me to go to the app and click restore purchase so somehow it linked with you guys, however I did not sign for any subscription and now I'm being charged $9.99 on a weekly(!) basis and there is no way to cancel it as it doesn't show under the Settings > Subscriptions.

I'm desperate because their support doesn't reply, even though I've submitted many tickets to them (18098, 20865, 20869) this clearly is a fraudulent nature as can be seen by many other victims if you scroll down this page:

https://justuseapp.com/en/app/1459969523/nebula-horoscope-astrology/contact

I'm begging you to help me and others in this case

Best,

Seva

[Re-Titled by Moderator]