Not sure 100% what you mean.
If you're talking about an option on the menu (regardless of whether it's labelled as a "asian vegetarian meal" or not) running out early, then I guess there's little they can do - they only load a certain number of each menu and once it runs out, it runs out. You would just have to order the vegetarian meal as a special meal in advance.
If you're saying that your special meal order is being given to other people and you go hungry, then of course you have a cause for complaint. But I'm not sure whether this is what you are actually talking about.
Which is it?
