Its usually wait for a period of time and try the password recovery. If you can’t recover the password, you might need to factory reset to get back in

As you are facing difficulties in connecting to your Wi-Fi name and password. Try doing the Factory Reset and connect to the default Wi-Fi name and password which is available at the bottom of the device.

Please follow the below link for “Factory Reset “ and “Finding the default Wi-Fi name and password “

http://arris.force.com/consumers/articles/General_FAQs/SBG10-Factory-Reset

http://arris.force.com/consumers/articles/General_FAQs/SBG10-First-Time-Installation

 On the First Time Installation link please check for the Wi-Fi name as SSID and password as Wi-Fi security key 

Make sure that you type the Wi-Fi password without any space and try “Upper Case” and  “Lower Case “ alternatively letter if available.