MAC'S PLUMBING & PIPELINES PTY LTD

I engaged macs to install a taylex septic system, job was completed over 12 months ago and paid in full on completion. Council have emailed me saying my system is not compliant and I cannot use the septic tank as MACS have not submitted as built drainage plans. I have tried multiple times to have them complete this over the last 3 months, I messaged saying legal action will be taken within 3 business days if not completed, and the owner called me calling me a C, he doesnt need this S, repeatedly asking whats the problem, even though i keep telling him what he has to do (submit his drainage plans, part of his job). It is beyond me how the Taylex market is taken by this ridiculous excuse of a company. 12 months after paying completion of the job, I have a note from council saying I can be fined $37000 for using my toilet because it goes into the system this muppet installed.