Charterquest horrible service

I have the most horrendous experience with Charter quest. First they promised to get a lecture to assist me with re-writing of my exam which they never followed through. I had also had a mix up with my exam booking after I got misleading information information from their stuff member, they absolved themselves from the situation and I'm left with a bill to pay and unwritten exam. Now, they are refusing to respond to my email asking to withdraw my studies with them.

Dealing with them is a nightmare. They always promise to respond to queries which they never do or take forever if they decide to.