Really bad service

Today I have made THREE orders and each of them were unsuccessful! The first two were because items were out of stock, but they do not tell me which items are not in stock so that I can make my order again excluding that item. I then called Mr Delivery to ask what was not in stock and they told me to phone the restaurant to find out myself and they gave me the number. Firstly, why is it my responsibility to make this call?? Why am I using Mr Delivery if they won't make my life easier? Secondly, I called this restaurant and they did not answer my call after calling them three times. The third order the business never responded after waiting forever. This is just absolutely pathetic and they have lost business today because of it.