Your service provider might be throttling your WiFi service based on your use. If you have a centralised provider like AT&T or any public utilities company this can be a problem. Happens a lot with cell phone providers as well. A dedicated 5g internet connection might help, But learning to disable this feature is also not so complicated, But needs some technical know how if you want to go the shadowy coder route. https://youtu.be/YBrboZy00KA?si=ZWe_5xslS7dUylAe