Detecting when uplink is not received

Hello guys,
Anyone knows the proper way to detect when the uplink is not being received by the Lorawan server?
i have the TXConfimration ON but i can’t seem to find a proper way to know whether the uplink has been received or not and react based on the return…

using the downLinkAckHandle() is not being triggered when the uplink fails… it only triggers when the uplink is received.

Using HTCC-AB01

Anyone done this?

cheers,
Jay