It’s wise to have two-factor authentication enabled on both your Luno account and the email address associated with your Luno account. If you use Gmail, use Google’s Gmail security checklist to ensure your email is safe.
Read up on locking your account
Change your password
Revoke API keys in Settings on web
Report the suspicious transactions via the link in one of your payments emails
We cannot restore your digital currency (Bitcoin or Ethereum) if it has been stolen. Rather be safe than sorry.