Title: Multiple Zigbee devices silently stopped communicating – devices still present in Z2M, rejoin without deletion fixes them

What happened?

Setup: Zigbee2MQTT 2.14.1, zigbee-herdsman 10.9.2, SMLIGHT SLZB-MR1U with CC2652P7/Z-Stack over Ethernet, Zigbee channel 11, Home Assistant + MQTT.
On September 15/16, several Zigbee devices suddenly stopped communicating without any intentional configuration change.
Multiple SONOFF SNZB-04P contact sensors stopped reporting their state and a HEIMAN HS2WD-E siren stopped responding to commands. However, all devices were still present in Zigbee2MQTT with their original names/IEEE addresses, and cached battery/LQI information was still displayed.
Other devices on the same Zigbee network continued working normally, including some SNZB-04P sensors and a FRIENT KEYZB-110 keypad. Zigbee2MQTT, MQTT and the coordinator were running normally.
Testing the HEIMAN siren directly from Zigbee2MQTT (warning/emergency) produced no response, ruling out Home Assistant/Alarmo as the cause.
Fix: I enabled Permit join and put each affected device back into pairing mode without deleting it from Zigbee2MQTT. Each device immediately started communicating again, while keeping its existing name, entities and Home Assistant automations.
After doing this with the affected contact sensors and siren, the complete alarm system works normally again.
It therefore appears that the devices were not actually removed from the Zigbee network/database, but had somehow stopped communicating until they rejoined the existing network.
I did not change the Zigbee channel, PAN ID or coordinator configuration before the problem.
Has anyone experienced similar behaviour, particularly with Zigbee2MQTT 2.14.1 / zigbee-herdsman 10.9.2 or CC2652P7 coordinators?

What did you expect to happen?

No response

How to reproduce it (minimal and precise)

No response

Zigbee2MQTT version

2.14.1

Adapter firmware version

20240710

Adapter

Zstack

Setup

Home assistant thrue Docker in DSM

Device database.db entry

No response

Debug log

No response

Notes

No response

Start by reproducing the behavior with Zigbee2MQTT 2.14.1, zigbee-herdsman 10.9.2, the CC2652P7/Z-Stack adapter, and the affected device types. Collect the missing debug log and database.db entry, then determine why devices remain present but stop communicating; done means the cause is identified and a reliable fix or diagnostic path is established.