Disappointed with lack of assistance

We were approached by Innovation Hub Group regarding the installation of an inverter at our offices. At first the inverter did not have any troubles. Now we have been experiencing severe issues with our inverter and have been requesting Innovation Hub Group for assistance. We were promised assistance but to no avail. For the past two weeks the issues with our inverter has intensified and over and over have been requesting assistance. Suddenly now Innovation Hub Group does not have the technicians at hand to be able to assist us as their technicians do not have the necessary knowledge to assist us and they have to source a technician (which we have to pay extra for). We were not informed that a technician has to be sourced and paid extra for as this was not conveyed to us when the contract was signed. We were told that they have experienced technicians who will be able to assist us if needed. They would have supp**** us with a quote to have another technician (not from their offices) to assist us with our inverter, but to no avail. We are very disappointed with the absolute lack of assistance from Innovation Hub Group.