Custom Button to Update a picklist field

Hi there,

I'm trying to create a custom button that will update a picklist field.

It's giving me the return message but not updating the field. Any idea on what's wrong?

I'm currently using this code:

mp = Map();

mp.put(CustomerStage,"Churned");

updateRec = zoho.crm.updateRecord("Accounts",AccountID,mp);

info updateRec;

return "The cancellation workflow is now in progress, please update the Cancellation task.";