Update Person metadata of uploaded documents

Forms SharePoint Online
6

Dear @danlim26,
Okay, and if you try adding the following before update, will you get the correct user ID in alert?

...
alert(fd.field('Approver1').value.EntityData.SPUserID);
library.items.getById(itemIds[i]).inBatch(batch).update({
    Approver: fd.field('Approver1').value.EntityData.SPUserID
 }, "*", entityTypeFullName);
...