Try rebooting your router. If you are not sure how to do this, you can unplug the router for about 20 seconds and then plug it back in - allowing sufficient time for the router to reset to its previous state. In Windows 10 you can go to the search box and type Network Troubleshooter - as the utility runs, select Identify and repair network. If neither of these actions resolve the problem, you will need to seek additional support assistance.