Hello.
I have hap ac, 6.45.6.
Just bougt d402 tele2 modem, and it did not detect in interfaces. Led is work on it, USB is work also on the router.

There is no info about the modem, just https://4pda.ru/forum/index.php?showtopic=943224 and that it is on qualcomm 9615 and has a web interface.
In windows in detects as a USB LAN card.