Laravel Nova Multiselect (on create error Array to string)

[vmind]

Hi.
Im try using MultiSelect when creating record but I get error "Array to String".
But when I update record everything is ok.
The code is the same. Also I paste code from the docs and error is the same.

Panel::make('Material', [ MultiSelect::make('Select materials', 'material_id') ->options(Material::orderBy('name', 'ASC')->get()->pluck('name', 'id')) ->hideFromIndex(), ]),
Thanks