@nameisnani 

try this and replace your correct variable name

${current.variables.requested_for}

If the above doesn't work then

you can store those variables in workflow scratchpad and then use in notification like this

1) run script

workflow.scratchpad.requestedFor = current.variables.requested_for;
workflow.scratchpad.deviceStolenDate = current.variables.<dateVariable>;

2) in notification message use like this

A lost or stolen device has been reported by ${workflow.scratchpad.requestedFor}
The device was lost or stolen on ${workflow.scratchpad.deviceStolenDate}

If my response helped please mark it correct and close the thread so that it benefits future readers.

@Ankur Bawiskar @SN_Learn 

still error is coming 

This is my mail script 

(function runMailScript( /* GlideRecord */ current, /* TemplatePrinter */ template,
    /* Optional EmailOutbound */
    email, /* Optional GlideRecord */ email_action,
    /* Optional GlideRecord */
    event) {

    var requester = current.requested_for.getDisplayValue();
    var date = current.variables.date_item_was_lost_stolen.getDisplayValue();

    email.setSubject(current.short_description_1);
    template.print("<p>A lost or stolen device has been reported by " + requester);
    template.print("<p>The device was lost or stolen on " + date);
    template.print("<br />");
    template.print("Description:" + current.description_1);



})(current, template, email, email_action, event);

This is the catalog

Short description and description we are getting from variable set 

You can see in the notification preview short descp and descirption are shwoing undefined ,  

@Ankur Bawiskar @SN_Learn 

can you please tell me what was the mistake here and what correction required .

You are missing the variables before the varible, have a look at updated code

(function runMailScript( /* GlideRecord */ current, /* TemplatePrinter */ template,
    /* Optional EmailOutbound */
    email, /* Optional GlideRecord */ email_action,
    /* Optional GlideRecord */
    event) {

    var requester = current.requested_for.getDisplayValue();
    var date = current.variables.date_item_was_lost_stolen.getDisplayValue();

    email.setSubject(current.variables.short_description_1);
    template.print("<p>A lost or stolen device has been reported by " + requester);
    template.print("<p>The device was lost or stolen on " + date);
    template.print("<br />");
    template.print("Description:" + current.variables.description_1);


})(current, template, email, email_action, event);

Mark this as Helpful / Accept the Solution if this clears your issue

@Ankur Bawiskar @SN_Learn 

I have checked in email logs , there is no email sent

@Ankur Bawiskar @SN_Learn 

can you please tell what was issue here .