Mking Long Text Box as mandatory

Hi

Can you please advise, what development is/are required to make Long text box mandatory .

I am working on requirement where we did development and added 5 different questions in Long text box of IW24. Answer of those questions, user has to record while creation of Notification.

There are chances if Long Text is not mandatory, then user can miss to record it.

We want this field to make mandatory.

Thanks

Sudip