How do I factory reset my modem/router so I can reset the password to get into it?

Thanks for the response, I have the CGM4141 model. Hello to a fellow RI'er

Ahh, the black one. According to the support page, the reset button needs to be held 10 seconds for factory default. 

On a separate point, may I ask why you are renting the gateway and not using the router part? Why not buy your own modem too? Do you get the gateway for free with your contract?

Thanks, I had tried that I'll have to try it again.

I had my own modem and router was having issues with my service that started with a problem cox maintenance found on the line outside. They kept blaming it on my modem so I had to get theirs to prove it wasn't my modem causing the issue. It's in the area I guess.

so I had to get theirs to prove it wasn't my modem causing the issue.

Ahh I see. That makes sense. It is hard to get things properly escalated to maintenance. Hopefully with the gateway, they will have nothing else to blame. Good luck.

Thanks