Sample Parameters for getEndDate global function in app composer trigger

Dear experts,

Request you to pls share a sample function call parameter for "getEndDate" global function in app composer trigger. I am trying to calculate enddate from a given date by adding Duration and duration Unit to it

For me I used below parameter values as per guidelines but not working.

adf.util.getEndDate(now() ,3, 'MNT', null) ;

Below is the navigation

App Composer > CRM Cloud > Subscription Product > Server Scripts > Triggers > Before Update Triggers > Function > Global > getEndDate

Regards,

Rajesh