Start here:
If you think your Apple ID has been compromised - Apple Support
Change your password ro a new and unique value, and enable two-factor authentication, and confirm your trusted numbers associated with your Apple ID are correct, and ensure your password-reset oath details are also secure—your email access passwords, if different from your Apple ID.
For more:
https://help.apple.com/pdf/personal-safety/en_US/personal-safety-user-guide.pdf
Contact your financial providers and explain the situation with them, particularly if these folks have access to your accounts.