Worst Worst Service

I have logged numerous complaints/request for feedback regarding my refund. So far not 1 phone or email to apologies for the inconvenience caused. They refuse that you speak to a Manager or even the manager refuse to call you. How do I logged a complaint against a ISP company that has no customer service ethical compliance to a customer. This is my worst customer experience ever, at least the other companies will call you back. Please help me escalate this matter so that someone can take responsibility for their pathetic service.