Finest Dental review: treatment

Throughout my treatment I have never had a set dentist. My treatment was supposed to end in September but it is now February and I have not received my SECOND set of refinements, which I need as one of my teeth is set significantly behind the others still. My appointments are cancelled or changed without warning and often when I go to them the dental staff do not know what I am there for and I have to try and explain. My last set of attachments were not removed fully and so my teeth are rough and still coated with dental glue. I can never get through to anyone on the phone and despite passing on messages through the hotline my calls are not returned.
I have complained twice before but did not receive a reply to my last complaint. I am one step away from seeking legal advice as I am not even sure this isn't just one big scam.