Can you try restarting your dev instance, as per my experience before, if we do any changes to Apache jackrabbit oak TokenConfiguration it will show authentication failed message.
After restart it should work properly,and the value you have edited 43200000 should be saved. Also check your error logs if you see any other error. If the issue still persists, please do check the error logs, what kind of error it is throwing. And one more thing what was the value of the Token expiration before you have edited it?