Hi,
I try to set the Author field on an Item but I get everytime an error "Uncaught [SharepointPlus 'setReadOnly']: the list ID/Name is required"

I try this at the end:
$SP().list("Listname").setReadOnly("Author", false)
.then(function () {
$SP().list("Listname").update({ ID: 1, Author: 1478 })
});
I tried the same with add but I get the same error.

Thanks in advance