Ignores Requests to for Service

I have tried unsuccessfully to contact this company. Every phone number ends with leave a message. One day I got through and was told that I must write to *** and only then can I be helped. I have written twice to this address and received radio silence. My father is old and struggles with anxiety. His tax for 2020 cannot be completed because of a mistake on the IRP 5 form. I have called sars and even have given this NMG all the details. THe date of Accrual was 31.05.2019. It was not listed on the IRP5 that was submitted for 2020. The Lady at SARS says the number for the Directive is ***0 and the source code was 3915. Why doesn't this company fix their mistakes or respond to their client. It was them who made the error on the IRP 5 form. My father is incurring penalties from SARS and he is a pensioner who is very sick. Please can someone help us.