Forza Horizon 4 Problems

Hi. While playing Forza Horizon 4, some problems that did not exist before started to appear. For example, when moving fast, everything seems to slow down and then speed up suddenly. It’s like internet lag but my internet is enough for it. There are some problems while loading the map as if it is not fully loaded. I’m getting a bandwidth warning. Can you help me? My monitor is 75hz 1ms, thanks in advance.