UPS express pathetic service

I am receiving a parcel from China, via UPS. I was phoned for my ID number and email address before it arrived in SA, but never received an email to make a payment for the duties. I eventually phoned them and received the invoice, which I paid and sent a POP via a reply to the person's email. (This was 03-03-2021) I sent emails to the same person a day or 2 later, asking when the parcel would be delivered, because the tracking showed that it was already in their warehouse for some days. They reply I received was a request to send the POP, which, as mentioned, was sent on the day the invoice was sent to me. This was now 11-03-2021. To this day (15-03-2021) I have not received a reply or my parcel from them and the tracking is still showing that they are awaiting payment of duties!