Pure group dishonoring agreement

I was referred to them by my client with same problem of previous telecom/ voice recording system . Both has had endless issues ,but I was told I could use old phones and switchboard, when technicians come onsite it had to be replaced with new system. Management said do not warry, we would credit your account because they knew I still had to pay old contract. this was never done , but they did it for my client. We had same problem and same previous contract. This has been going on for months and I send emails to management , but nooo response! I have to pay both suppliers and the new company do not honor our agreement!