Could you check, if you can reach device's WebUI using a different browser, after clearing browser's cache or in browser's incognito mode?
Otherwise, could you try logging to the device via SSH? Download PuTTy client (link). Open it:
Use the following details:
- Host name: 192.168.1.1
- Port: 22
- Connection type: SSH
- Press Open.
Enter root as username to login and your router's password, which might be the default router's password, if you have performed a factory reset or installed firmware via bootloader.
If you were able to login, execute the following command:
This will generate a troubleshoot file. Now, to extract this file from the router, please download WinSCP. Install it and open.
Enter following session details:
- File protocol: SCP
- Hostname: 192.168.1.1
- Username: root
- Password: <routers_password>
- Press Login
Navigate to /tmp folder, you should find troubleshoot file. Move it to your PC and attach it by editing your question.
The logs in the file might provide more insight into the issue.