Sub standard fibre support

On the 28th of April 2020 I requested an upgrade on my Fibre from 20/10 to 100/50. Within a few minutes the confirmation came through, and I was set. Although I only got about 50mbps download... On the 29th of April I contacted Afrihost, explained the situation, they refreshed the connection and I was getting around 97mbps download, happy. The last few days I am only getting, at most 40/20. On the 6th of May I contacted Afrihost again, they said they had an issue on the line, and that can take up to 48hrs to resolve. Today, the 8th of May, I wanted an update, and now they're saying my 100/50 line will only be applicable from the 1st of June 2020 because the 'free upgrade' on my 20/10 line has already been put through... Even though I have already been billed for the 100/50 line, and they charged me Pro-rata from the 28th of April. So, I am now paying for a line that I am not even getting HALF the speed I should... best of all, it WAS working perfectly at 100/50. Apparently, the 'fault' submitted on the 6th of May, was closed by the technician, and now everything has to start all over again, 24-72hrs to be resolved... I expect his to be resolved still today. Either my speed is fixed, OR I get refunded for this waste of time.