Try thi s

function onLoad() {
var currentUser = GlideUser.getUser();
var fieldA = g_form.getValue('requested_by');

fieldA.setValue(currentUser.getID());
}

if you get answer please mark helpful and accept solution

Hi @Hm10 ,

The syntax you shared in the question description for default value works well in my instance.

You can try checking if there are any other catalog client scripts or UI policy might be clearing that value.

Please let me know if anything else is needed.

Hi @Hm10 ,

Please follow the steps below to populate the logged-in user in a reference field:
1. Right-click on the field and navigate to 'configure dictionary > go to the default value and type as below:

2. The second way to setup the same in catalog item is explained in the below link:

Get User Details based on the Logged in user/ User selected in Client Script 

Please accept my answer and mark this helpful if it helps.

Hi @Hm10, 

If you want the client script to set logged-in user value use the below syntax

function onLoad() {

    g_form.setValue('req_for',g_user.userID);

}

OR simply you can use  g_form.setValue('req_for',g_user.userID);  anywhere in client side.

For server side:  javascript:gs.getUserID();  in the default value

Please mark as Accepted Solution & Helpful 🙂