Complaint- Cancelling my order with no explanation

I currently have a 4MBps ADSL line at home.We do not have fibre in our area yet. I requested/ordered an increased line speed on the 1st of April 2020. This was to increase the line speed to 20Mbps. I tried following up on the 8th April, bearing in mind that the website says the order will take up to 5days. I didnt get to speak to anyone but left my number. I then got a call at 16:16 on the 8th but could not answer the call as I was in a meeting. When I called back the lines were already closed for the day. Today 9th April I received an sms saying that my order has been cancelled. NO EXPLANATION!!!!!!! I Wen to check the order online and it was missing. I then ordered a 10Mbps line and called in to try and follow up on why my 20Mbps line order was cancelled. The Advisor on the call hen said It was cancelled because my area doesn't support a 20Mbps line. This hnestly just ****ed me off. I asked why I was able to order it on the website in the first place and I said I need my 10Mbps to be activated sooner than the 7-10days that she told me it takes. If this was telkom or any other ISP I would not have been able to order something that my area doesn't support. I am a developer who needs to remote into my clients environments and with a line speed this slow and 4 people in this household working from home the connection drops. I've missed out on work because of this. If I cannot work I cannot sustain my family. I asked to speak to a manager and she told me that I cannot and I woill have to wait 7-10 business days for this to be processed. I need this sorted TODAY!!!!