Online purchase not as advertised - 1 of 3 items missing

I ordered a packaged deal on line - stroller, carrier and base. Received the stroller and car seat, but not the base for the car seat. Have logged a request online with babies r us - indicating the deal as advertised and purchased were note delivered. I received an email with the indication that I will received feedback with in 36 hours.

There has been 3 working days since, but no response.

I also called and gave ref of email received - they acknowledge the request and indicated a response to the email confirming that the base will be delivered will be done, still awaiting that response.

I tried to call them again twice, send from pillar to post between reception and the customer services department - since no once answer when customer service is called.

Please could this be sorted out and the delivery arranged - my child is about to arrive, but still awaiting customer service replies??