Stanlib do not reply to you regarding your Unit Trust Investments

I have an investment with Stanlib Unit Trusts, i did send an inquiry already on Monday 31 July 2023,and no response. I phoned them and waiting 8 min 32 sec on the phone only to hear that no this Department can not help me, because it is regarding my Tax IT3(b) and i need to send an e-mail to the particular Dept. Already did send a mail and still no response, and response e-mail said within 24 Hours the will get back to me ?? how is it possible that the IT3(b) dept do not have a contact number or nobody gets back to me regarding my IT3(b) Certificates ??