Hey there @Grefsheim05 - sorry to hear about this.
Have you tried using our self-served look-up tool to identify the email address that's associated with the charge?
If not, could you give it a go and let me know if it helps at all?
Otherwise, you can submit a ticket to our support team through this form. Just make sure to use an incognito window without signing into any Dropbox account.
I hope this helps and please keep us posted!