how to show different content in email and in-app notifications

we have a requirement to show different content for in app and email notifications of RESIGNATION.

So I used below condition in the RTF template using the oracle docs.

<?if:BINDISONLINENOTIF='true'?>

In app content

<?end if?>

<?if:BINDISONLINENOTIF='true'?>

Email content

<?end if?>

But it's not working. Please help me to acheive the requirement.

Thanks,

Dara Nagasai