@mwarren91 Welcome to the forums. Try this:-
1. Connect a device onto the router's WiFi or plug a laptop/PC into the router using an ethernet cable
2. Go to the router's homepage at http://192.168.1.254
3. Click on the Advanced Settings tab
4. Type in the admin password found from the back of the router and click the OK button
5. Click on the Continue to Advanced Settings button then the Broadband tab
6. If there's a Disconnect button, click that
7. Change the username to the broadband username in the format of firstname.lastname@example.org If you can't remember this I'd check for any emails PLUSNETsent you as they'd add the username to the top of the email.
8. Type in the account password, this can be reset here: https://www.plus.net/forgotpassword/ if needed.
9. Hit the Connect button.