I got charged 54 dollars 6 times in a row

Furthermore this Apple support Billing Article may answer your question.

Subscriptions and Billing - Official Apple Support

Also check Settings, your name, iCloud, Manage storage, change storage plan 

Also

 reportaproblem.apple.com.

Individuals can only access your applr account if you leak your Apple ID password, so it may be a good idea to change it.

Accessing your Apple account will not allow fraudulent billing so contact the agent who billed you, or your card bank, or Apple Support.

Depending on your region, you may be able to reach them here: contact Apple Support