v4 Rendering Relation Manager in a Modal not working

->modalContent(function (InventoryItem $record) {
    return ViewField::make('unitConversionRelationManager')
        ->view('filament-panels::components.resources.relation-managers')
        ->viewData([
            'managers' => [UnitConversionsRelationManager::class],
            'ownerRecord' => $record,
            'activeManager' => '0',
            'pageClass' => static::class,
        ])->render();
});

->modalContent(function (CustomForm $record, Schema $schema) {
    // Calendar availability relation manager
    return Livewire::make(CalendarFieldOptionsRelationManager::class, [
            'ownerRecord' => $record,
            'pageClass' => static::class,
        ])->key(CalendarFieldOptionsRelationManager::class)
        ->container($schema)
        ->render();
});