Check for the status of the network by accessing the Settings---> Network and check connection. You must also solve the connectivity issues by providing the correct name of the Home network and enter the password correctly. Now, check whether the wireless router performance is good or else try to restart the router. Use the guidelines stuck on the router to restart it. Now, locate the router near the Roku device to improve the signal strength and to stream without buffering. Also, try to restart the Roku device by accessing Settings--->System---> System Restart and check whether the Roku won't connect to wireless network issue persists .check https://www.roku-com-link.info/roku-wont-connect-to-wireless-network/