Problem with Zigbee2MQTT and autodiscovery(???) - all the devices becoming unavailable after Z2M res

[hollow hollow]

Hi. For long time i had Zigbee2MQTT, together with other MQTT based integrations all working perfectly fine. MQTT is the HAOS addon, Zigbee2MQTT is external service connecting to it.
Unfortunately a couple of weeks ago i have accidentally wiped my Zigbee2MQTT config without a backup. I have managed to restore it from the Zigbee2MQTT logs (Zigbee config, device names, etc) and Zigbee2MQTT is working perfectly fine again... but the devices are often unavailable in HA. A combination of restarts of Z2M, MQTT server and Home Assistant usually makes them work again until the next Z2M update and restart which results in all the devices becoming unavailable again.

When im looking at the MQTT messages, the states of Zigbee devices are always being updated fine, so somehow it must be related to Home Assistant, but im not sure how to troubleshoot it.

Im attaching the diagnostics file for one of the Zigbee switches which is now unavailable:

[hollow hollow]

in fact, while ive done it previously, now i cannot find a combination of restarts which will make HA see Z2M devices online

[hollow hollow]

What i havent noticed immediately is Z2M not sending autodiscovery information in some circumstances even with it being enabled.