Please can you tell me why with the current code structure there is an error at @(LoadDataAsync() )

[Hunglmc]

@inherits LayoutComponentBase
@inject Microsoft.Extensions.Localization.IStringLocalizer<MainLayout> localizer
<audio id="notification" src="/media/notification.mp3" />
<BodyElement CssClass="my-5" />
<MudDialogProvider />
<MudSnackbarProvider />
<AuthorizeView>
    <NotAuthorized>
        <CascadingValue Value="hubConnection">
            @Body
        </CascadingValue>
    </NotAuthorized>
    <Authorized>
        @(LoadDataAsync() )
        <NavMenuMobile />
        <div class="flex mt-[4.7rem] md:mt-0">
            <NavMenu />
            <CascadingValue Value="hubConnection">
                <div class="content">
                    @Body
                </div>
            </CascadingValue>
        </div>
    </Authorized>
</AuthorizeView>