We have recently seen an increase in Just Eat accounts being compromised. Because of the ability to easily save your card details within Just Eat for next time, compromised accounts are being fraudulently used to order food.
It is important not to use the same password for multiple accounts. Even more so when accounts have payment/card details saved. You can set a unique and strong password by using three random words. You can increase the security of the password even more by adding in numbers and special characters.
Just Eat doesn't have Two-Factor Authentication, but if it does become available in the future we would recommend enabling it immediately.
You can check if your accounts and/or passwords have been compromised by using have I been pwned. https://haveibeenpwned.com/