Threatening with handover for a cancelled account

<p>Cancelled my account in September 2015 as I was heading overseas. They have not cancelled it and keep charging sub fees and penalties and are now threating to blacklist me.Alas, they do not respond to emails, their online chat keeps disconnecting and even if you get a full conversation they tell you to phone, and it is impossible to phone them from London.</p> <p> </p> <p> </p>