cancelling new package under 14 day period

I'm having a absolute nightmare with VM, rang last week to simply add the home works package , the whole call turned into a upsell and lengthy process (almost a hour and half on the phone), long shot was they could only add home works by amending other aspects of my existing contract. Because I was so desperate for the home works package I agreed but on reflection decided i would cancel under the 14 day cooling off period so rang them at the weekend, 2 days later, they couldn't deal and said it would be passed to their 'back office' .Since then i have been emailed my new contract/list of services and I've lost more than I had even been told and still no phone call back to resolve this issue. Struggling to find out the most basic of information, cant even find a straight forward email address for complaints. I've not used the home works package or the 02 sim they insisted they would need to send! (Even though I told them I didn't want it) On reflection this whole experience has taken a a huge amount of time/ energy/ going to cost more money and I'm still no nearer to just going back to my existing package! Is there a department I can email to say I don't wish to proceed with the new contract? conscious of time ebbing away.  I really don't want to spend countless hours trying to rectify something that should in theory be straight forward. Any advice/help greatly appreciated.