Considering you said that you purchased, and then returned a WiFi extender, it might be that your computer is too far away from your router. Maybe try using a LAN cable or moving your laptop/ WiFi enabled desktop closer to the source of your WiFi. This may improve your latency and connection quality between your computer and router.My parents have not downgraded our internet plan, and restarting the router will only stop the lag spikes for about 10 minutes. However, recently we got a wifi extender, but since it wasn't helping we returned it, and I have gotten the worst lag spikes ever since. Do you think this could have anything to do with it?
Not many people use my internet. I've tried restarting my laptop, but the lag spikes return sooner or later.