Unable to update the Recipient record using Javascript xtk.session.Write in WebApp using ACC V8 client console
Hi Team,
I have created WebApp with Input Form with FirstName, LastName, Email in 1st page. And some Check box inputs in 2nd page.
my WebApp workflow configured like below.

1st page Input Values should Update into Recipient schema. But its not working with below script.

// Update RCP Data
var id = ctx.recipient.@id;
var ID_PARTENAIRE = ctx.vars.bp_id;
var Business = ctx.vars.bp_Business;
var Entity = ctx.vars.bp_Entity;
var currentDate = formatDate(new Date(), "%4Y/%2M/%2D %02H:%02N:%02S");
xtk.session.Write(<recipient xtkschema="nms:recipient" operation="_update" _key="@id,@ID_PARTENAIRE,@Business,@Entity" firstName={ctx.vars.updfirstName} lastName={ctx.vars.updlastName} email={ctx.vars.updemail} lastModified={currentDate} />);
Getting below Error once submit the Button in Form, stating Unable to find the Key values for element Recipient.

Note: we have Extended the nms: recipient schema and added custom columns as Keys. I am using those for Update or Insert Operations.
Other hand, same script inserting new record when I am trying without Key argument.
The Storage activity not helping to update, pre-loaded columns.
Can anyone help me solve this error.
Thank you.
