Very poor and unprofessional services

I have never experienced such poor and unprofessional conduct from a company that deals with multiple so called reputable Insurers, a quote was done by NetAssess for repairs to my vehicle, I then booked my vehicle in for repairs and repairers advised NetAssess that the quote was not 100% correct as there were unforeseen additional damages due to the accident and the vehicle was then fixed fully and completed. However NetAssess did not notify the Insurers of the additional costs and now my vehicle was completed on Thursday the 11th of September 2025 but I cannot collect my vehicle from the repairers as the Insurers have not paid for the additional costs and now I have to suffer for their unprofessional conduct. There is no communication on the progress of the payment and no explanation has been given as to what is going on.