Poor online service delivery

I have placed an online order on 12th January and was pleased when the delivery was made within 3 days. However. that was the last pleasant experience. The item delivered was wrong. The delivery team took it back to the warehouse and said I will receive the item in another 3 days. After 2 days I received a sms to confirm delivery, yet every morning from then onwards I received another sms to move the delivery date. On the 19th another sms to confirm delivery for the 22nd of January. I phoned the online customer care to enquire about the order and have asked to be updated on the status, but have not received any feedback. On the 22nd of January I again did not receive the delivery (and no update). I again contacted the customer care number and the lady told me the item is out of stock at the warehouse. I asked to speak to a manager and she promised me that someone will phone me back. I did not get a call back and had to phone again later to speak to someone so that I can get information on the status. This time I was told the order is scheduled for the 24th of January. I still don't know what the real status of the order is as I get different information every time I phone. I have one again requested to receive feedback, so lets see if this would happen. With every call I have asked for urgent delivery as this item is needed to care for a patient, yet I am still waiting....