item missing from order

I ordered some items online on the 21st March 2018 (order number ********** 91) as I'm going overseas and needed this for my holiday. I received my parcel via the courier at my office on the 26th March 2018. Upon opening the box and checking all the items I found one item missing. I immediately called their customer care and advised them about this. They took down the order number and said they would escalate my query to the online team. I have since followed up 5 times with no success. All I get is automated e-mails and no resolution. How can a parcel be sent to a customer without being checked properly??? This is absolutely shocking. I was very sceptical about shopping at Edgars online and now my worst fears are coming true. I need my item sent to me or a refund issued.