Shocking customer service

Absolutely shocking customer service - no reply to emails, callback request, queries submitted through the website. My query has been going on for a month with no resolution & every time I get the odd reply (from someone different every time!) they don't know what the issue is & I get the standard 'we'll get back to you' response which of course means radio silence. My next step is to try cancel my subscription that's if I can get hold of someone as they very 'conveniently' don't have a telephone number!!