Stuck in Customs Clearance for over 2 weeks due to their clearing agents

I shipped a small package for my business from the USA and decided to use Fedex because they promise "express" delivery. My package was picked up on the 11th of June with the estimated delivery date of Thursday 18 June. The Monday 15 June I got an sms from Fedex asking for me to urgently send through my ID number or importers code to Palesa Mogadime and her email address was provided. Within 5 minutes of this sms I sent through my ID number. By the Thursday that it was supposed to be delivered the system showed "Clearance delay: No action Required" I then decided to wait since it said "No Action Required". By Monday the 22 June, I had still received no feedback and there was no change on the system. I then decided to call Fedex and when I reached customer service, they said that they were waiting for my ID and that no such info was added to my shipment. This was the first frustration I experienced. The customer service agent then loaded my info and said I would be contacted within 24 hours. The next day Palesa Mogadime emailed me to ask me for the Commercial Invoice of the goods, which I then sent to her and she too ensured me customs clearance can take 2-24 hours after receiving all these documents. I waited till that Thursday which was now 48 hours after, and phoned customer service again (because the number Palesa provides in her email which is supposed to be her direct line is not answered). This time customer service said that the item was stopped again, and is now detained at Port Health. I was shook, at what point would I have known this if I did not call myself. The customer service agent, Mark was very helpful and informative. The problem is they cannot do anything as they are only customer service agents and not the agents who are dealing with customs themselves. So once again Mark told me no action is required. The next day I decided to call Fedex again, I figured if I call every day it's better progress than not to call or just to wait. This time the customer service agent Lucia, said that customs has requested my Commercial Invoice. What!? It was sent that past Tuesday to Palesa but these "clearing agents" are not doing their jobs. Once again, if I did not call, who would've communicated this with me and by when?? I then emailed it to Lucia, called back and confirmed with Natasha (another customer service agent) that it was now updated. At this point I was upset as it seems the unnecessary delays were caused by the clearing or stop agents themselves. I then sent Palesa an email explaining how upset I was about these delays and requested urgent help with clearance, I also cc'ed her supervisor Candice Samsidy in. The Saturday Palesa rep**** with "The package is detained by Port of Health, Percy please assist". And she cc'ed Percy Tshililo in. That's it. No apologies or amends. Nothing. Since it was Saturday, I decided to wait till Monday (29th June) for a response from Percy. I got none. I then sent him a private mail asking for an update, what the procedure would be and how long it would take and got no reply. I then called customer service again, and they told me that my information was updated that Sunday and sent to Port Health. And that I can only count from the Monday another 24-48 hours. But I was given this info last Thursday already? Wow. I then rep**** to the thread with Percy, Candice and Palesa in to say that Percy is not responding to me can I get someone else that can urgently assist me. Palesa again responded with "Percy, kindly assist" Later that day he responded with "Good Day All" the package is at port health and that as soon as he gets feedback he will let us know. Till now, I am still waiting for feedback. Customer service just keeps advising me to keep emailing them for updates. My experience honestly has been the worst. I usually use DHL and I have never had problems like this. My biggest issue is the lack of communication and bad service I am receiving. It is completely draining. Considering the delay was originally caused by a Fedex error in the manifest I would have thought that the company would be keen to get my parcel to me as soon as possible. Or at least try help. But I just feel like a number at Fedex. They are also using the current pandemic as a reason or excuse for the delays. I thought of becoming a customer with them to bring in regular shipments, but I have definitely changed my mind. It will also be the last time I use FEDEX and will let my shipper know to not use Fedex for South African shipments going forward either, with a breakdown of my experience.