Delivered to wrong address

Dell changed the delivery date to one when i was on holiday,  i changed the delivery address to one where someone would be home to receive the laptop.  I called to confirm.  Laptop was not delivered on the predicted day so i called again.  I was told it would be delivered to the new address the following day.  It was then delivered to the wrong address.  Apparently it was left behind bush and the courier appears to have signed for it.  2 days ago i called dell and via sales and then got transferred to customer services who promised to get back to me last night,  no reply.  I also have an email support logged, no reply.  Today I am trying to get in touch with customer services directly, the sales team are not available and i can't work out how to best the algorithm and actually get through to customer services. Can anyone assist with the way to get through the telephone algorithm please? Thanks