You need a HomeKit enabled v2 hub part number 2243-222.
See http://www.insteon.com/insteon-hub-homekit/
It sounds like you have an original v1 hub which also of course does not support HomeKit. I believe it should be simply a matter of getting a new hub.
However please note that the Insteon HomeKit hub does not allow also using Amazon Alexa and other systems. Some other brands do allow using multiple standards for example the Philips Hue can be used with both HomeKit's Siri and Amazon's Alexa.