Natis documents not received 13 months after requesting them

We paid off my late sister's account in 2022 and requested natis documents on January 2023 they asked us to send them all required documents. We did and they confirmed that they received them. They asked us to pay a fee of R362 to transfer the ownership to the executor we did and sent an email with the POP and courier address they promised to courier the documents to the address we gave them. It's now 13months later and we still haven't received the documents, we've been sent from pillar to post with no one assisting us. I'm calling them almost daily and sending them emails to no response or getting any kind of help. Yesterday I asked to speak to one of the managers and was told they're in a meeting and couldn't assist me.