Putrid service!

As everyone knows, Christmas is approaching. I've ordered a dress online for my teenage niece that she really liked. The order was submitted on the 7th December and the estimated date of delivery was for the 15th of December. Still havent recieved anything and it's the 21st of December! Logged numerous complaints but all they keep telling me is to wait until it arrives. I am disappointed with their service! I'll never shop online with this company again. It's putrid. I've never recieved this kind of mediocre service from any other retailer