Question about MQTT data referencing

we are using older version of LoRa server (0.24.1) and we use the reference in MQTT tx and ack to correctly assign, which message got confirmed (we have it as column in our DB on MQTT client side).
We are planning to upgrade to latest version, but we are bit confused with new new format of MQTT messages where in tx and ack isn’t reference field.
How can we track packet in MQTT messages now between tx and ack topics?

Thanks in advance.

The best way would be to use the HTTP API. You will get the downlink frame-counter value as a response, which is also used in case of an ACK.

Thanks for response. As we don’t have the MQTT client side in our hands (it is developed outside) and because of this we can’t simply switch from MQTT to HTTP API.
Would it be possible to return some kind of tracking between tx nad ack(error) back to MQTT as was reference field?
Thanks in advance.