LIBERTY Can not even fix their own mistake - SARS on my Case

I have now been trying for almost 2 months to get Liberty to correct my IT3 tax form so I can settle last years taxes, and after 4 e mails and 2 phone calls with promises it will be do NO REPONSE what so ever. I keep getting messages from SARS to submit the relevant document to avoid prosecution, but what can I do is the service I received is so pathetic. At the end it will be my name down the drain because of a company that can not even address a simple request on mistake they made. What now?