Hi @StSS, welcome to the forum 
If you’re able to successfully ping then most likely the communication hardware connections and the main network setup are correct.
- I assume your onboard computer (Raspberry Pi) is still running the Companion software (rather than BlueOS)?
- Do you know which version you’re using?
- How are you trying to connect to the web interface?
- Does http://192.168.2.2:2770 work?
- Can you try clearing your browser’s cache, or try in an incognito/private window?
If that doesn’t work you can try doing ssh pi@192.168.2.2 (password companion) to see if you’re able to connect and log in over ssh (to potentially do some further troubleshooting), but it may be simpler to flash on a new image, or preferably install BlueOS