public async Task <Notification> ChangeImportant(string username, int nId, bool important)
{
var notification = await notificationRepo.GetById(nId);
if (notification == null)
{
throw new NotFoundException();
}
if (username != notification.Username)
{
throw new ForbiddenException();
}
notification.Important = important;
return(await notificationRepo.Update(notification));
}