AfriHost CANNOT provide consistent Internet

Ever since I got this 250mbps plan last September, the speed either caps at 100 mbps (D/L) or completely drops to below 10 Mbps during the evening. It is fibre that behaves like a SIM card network and is completely unreliable. Sometimes it gets so bad that I cannot even watch a YouTube SHORT. I use both Ethernet and WiFi but the performance of the AfriHost fibre is horrible on both connections. Even as I type this sad and honest review, the speed is below 100 Mbps. This happens for majority of the day and night, every single day. And yes, the firmware for the router is up-to-date and I have rebooted and I have checked for interference and I have kicked everyone else out the home network and tested it and I get the same horrible results. I have tried everything Afrihost have recommended in previous emails. But I keep being told the same thing. I am paying for something I cannot use.