Changing delivery dates

on the 10/04/2015 I ordered a chellino side by side twin pram on the daily deal specials,after I ordered I received a confirmation that it will be delivered to my address by the 15/04/2015,and bare in mind that i made the payment on the same day and it was a cash deposit at the bank to speed up the process.Today i receive a confirmation from them that it will be delivered by the 20/04/2015.I have sent several emails to them but no one botheres on calling me back,i spent more than 30 minutes trying to call their call centre today as well.I need them to fix this,I need this pram by the 15/04/2015 as they promised before and not on the 20/04/2015 as i cannot wait that long.They said the delivery is free atleast they have kept their promise on that one.