I suggest you keep a closer eye on your accounts if you have managed to let a subscription renew 25 times (200/8) without you noticing. The support article If you see 'apple.com/bill' on your billing statement - Apple Support and the related article Get help with charges from apple.com/bill - Apple Support explain how you can check your iTunes and App Stores purchase history, cancel subscriptions (remember that these need to be canceled at least 24 hours in advance), and track possible sources of unrecognized Apple charges you may see on a bill. These may be purchases by Family Sharing members, others sharing your card (such as a spouse or partner, or a second Apple Account you have; you may not see a receipt).
Apple’s position appears to be that people need to be proactive about purchases, canceling subscriptions at least 24 hours before trials end, and ensuring that others are not able to make unsanctioned purchases on a user’s account. Note that if you allow—intentionally or not—another person access to purchasing on a device, or through Family Sharing if you are the Organizer, you are taking responsibility for things they do. Apple offers these features to help you avoid this situation:
On your device you can use Screen Time to prevent unintentional or unauthorized purchases from the App Store, in-app, and other Apple services. —> Use Screen Time to turn off in-app purchases on your iPhone or iPad - Apple Support
Also on your device, require a password for App Store and iTunes purchases —> Require a password for purchases in the App Store and other Apple services - Apple Support
Use Screen Time as part of parental controls on your child's iPhone, iPad, and iPod touch —> Use parental controls to manage your child's iPhone or iPad - Apple Support
If a child made this purchase on their device as part of Family Sharing, consider activating Ask To Buy—> Approve what kids buy with Ask to Buy - Apple Support
Use Guided Access to permit a person to only use a single app —>
Lock iPhone to one app with Guided Access - Apple Support
Apple will make a goodwill refund on occasion but they are not obliged to give any refund at all. For subscriptions, people post here saying Apple will perhaps refund the most recent one, but I doubt you'll get 25.
If you tell your bank not to pay what you owe, Apple will probably prevent you from downloading any more apps or updating any apps until you pay what you owe.