Removing dd-wrt firmware and restoring to factory condition

Hi, I have a Nighthawk R8000 which I bought with DD-Wrt firmware installed. I would like to remove that firmware and restore to a factory configuration. I might have messed things up. I selected the Factory Restore option, it downloaded some firmware and rebooted. Now, I can't access the router at all. It is attached to a Cable Modem provided by my internet provider and I have found it with an IP but when I try to access it no luck.

Any suggestions?