Autopage getting details wrong for months - GATVOL

ABSOLUTELY GATVOL! Altech Autopage took over an existing client base from Nashua Mobile around November last year. Being a client of Nashua Mobile, I was part of this take over client base. They firstly incorrectly captured my details, including my email address to which my statement gets sent - therefore having my personal and transaction details sent to incorrect details - which is sent in an unprotected PDF format. That issue is ongoing, now 7 months later. Over and above that, I was contacted when my contract expired months ago and offered to either upgrade my handset or to move to a lower monthly fee - I chose the latter as I was not in need of a new phone. 3 days ago I got a call from Altech Autopage offering me an upgrade on my contract, and further to this they still confirmed my email address as that of the originally incorrectly captured details, to which I assume my statments are still being sent. This triggered me to check the amount I am paying monthly - surprise surprise, that has not changed to the lower fee I opted for months ago. I have tried emailing Altech Autopage several times, and given multiple instructions to their call centre to fix this, with no correction