Lost Access to email / account compromised

Hi,

I have another dropbox account with a different email. I lost access to the email and have reason to believe the account is compromised. I have also been logged out of all my devices, and I can't access the 6-digit codes that are being sent out either. I tried gaining access again by answering the security questions (last file uploaded, etc.) - while I remember most of them, unfortunately I was not able to answer them all. After two attempts, it tells me to reach out to a customer support email, but I am only a Basic user.

What can I do? I am a EU citizen, if that is relevant.