Are you sure that obs-websocket 4.9.1 is compatible with 30.0.2? Is there a settings menu for it?
Starting with OBS 28, obs-websocket 5 is part of the default installed OBS. But obs-websocket 5 is not compatible with 4.9.1 and OBS Notifier 1.0.5.
Just use the latest version of OBS Notifier (without even specifying the IP, only the password).