Delivery date keep moving with stock available

I have ordered ***3 and paid on 2 April all items where in stock on the system when order was placed, even as I am typing it shows all items to be in stocks. Was on the customer care line for 13.12 minutes and heard several times delivery 2 days outlying areas 5 days. Yet my delivery date keeps moving, I still don't have my items and they are promising 30th now. Why while there is stock and how sure am I, I will get it this time