How to help a user remember details they entered

[Waspman]

A local community sports club which is very popular, allows people to put their children on a waiting list, from a PHP page. It also allows them to modify details or delete from the list, by entering their email address and child name.

However they have had incidents whereby parents have managed to “move their children up the list” by deleting other peoples children, when they know email/child name.

Changed it so they had to enter email address and a code that was given when they first registered - but most people forgot code. Modified it so code was stored on a cookie, but then people tried to modify data from a different device

Can anyone suggest a way to get over this?

Thanks

[deepvyas]

I think instead of security code you could introduce security question in place and answer to them can be remembered by user for future edits, If any

[Waspman]

Isn’t it a fact that you get so involved you forget to think of the really simple answers?

Many thanks, it is so obvious!

[astonecipher]

two factor authentication. Use an email or sms to email a temporary code and they enter it. That way, if someone is trying to get into someone elses account, the account owner is notified.