Business ProfileforAvalara Inc

We were in touch with Avalara in December 2023 for exploring using their services. Thereby certain terms were decided between us, however they thereafter sent a contract and thereby an invoice which was not as per our terms. We contacted them again and they said they are cancelling this and sending a new contract, which never got executed.Now if the new contract was not signed and the integration never completed with them due to complexity of the same at their end, they never asked for any money thereby assuming they are following terms decided that invoice shall be raised once we use their software and integration is complete. After one year they raise an invoice to us of an amount double of what was agreed, stating services starting after a month, we reached out to them stating that services have not started how do we have an invoice and that too double of the amount. To which they state this is a new invoice which starts in April 2024, but you have to also pay the older invoice, if the older invoice existed why did you never ask for money of it, how can the older or new invoice exist when the contract was rescinded and no new contract signed. When did we agree for a new pricing, when I raised all these questions it went to deaf ears. Thereby they sent an email that our account and services are terminated 27 March 2024, what termination when services were never used? And how is it that they raise a new invoice for services starting 31 March 2024 onwards when they state they have terminated our account.Now they are harassing us by sending a debt collection agent to force us to pay for invoices we never agreed to, services which we never rendered and for a new invoice of a amount never agreed to for this year when according to them our account is terminated. I have attached the reply we sent to the debt collector, but it is still continuing the harassment. I have seen multiple customers complaint he same and for sure believe fraud is their very intent.