SHOCKING SERVICE - NO CORPORATE SUPPORT

I have recently added a new vehicle tracker to my corporate account and changed various tracker types. I was billed double for new ones and my entire invoice on 31 August was incorrect.For 10 days I have sent over 20 emails, made over 10 calls and left as many messages and still today not one person has responded or returned a call or email to correct my billing and pass credit notes and refund us. I am on the app to cancel my entire policy .