Upgraded to 100mbps but buffering like crazy

I upgraded my speed from 40 mbps to 100mbps costing me R897 pm but it’s still buffering like crazy especially when live-streaming the football. So frustrating especially buffering just when a goal is about to be scored. I thought fibre at 100mbps will cut out buffering completely. Vumatels fibre internet is ******* a ******* financially