Remember modem mode replaces 192.168.0.1 with 192.168.100.1, worth giving that a shot also.
Are you using a phone to access the settings? Sometimes shutting off data (3g/4g/5g) forces the phone to connect over WiFi which is what you want.
Finally, if you have a laptop/desktop, try the address again over ethernet. If all this doesn't work, worth trying a pin hole reset.