There is reset on the back of the router. Hold it in for about 10 seconds, till the lights flash. This will bring it back to default.
Before resetting the router, go to this link, select your model and the select Connect to Xbox live (network support). It will show you how to configure it.

http://support.xbox.com/support/en/us/nxe/default.aspx


Click on this link or copy and paste the complete link into your browser.
If I could be of further assistance, let me know. If this helps or solves the issue, please rate it.
Thanks, Joe


I’m happy to assist further over the phone at https://www.6ya.com/expert/joe_8b8c2cd6ce148309