Wireless Sensor Deleted after 3-4 hours of proper working

Hi. I have added a custom WirelessRssiDiscovery to Ios.php to poll my Cisco AIR-BR1310G wireless bridges (30+ sensors). It works fine after I run Discovery via webui, everything goes as intended, polling, graphs are fine — only for 3-4 hours, then they all disappear at once. Also, built-in “discoverWirelessClients” sensors don’t disappear but they all become zero at the same moment (I’m not sure if they behave like that from the box).

The only logs in the Device details are:

Wireless Sensor Deleted: rssi ios

What component deletes them all at once and how to tune them to stay?

./discovery.php -h HOSTNAME -d | ./pbin.sh
./poller.php -h HOSTNAME -r -f -d | ./pbin.sh

discovery: https://p.libren.ms/view/790ab426
poller: https://p.libren.ms/view/845c529d

Component | Version
--------- | -------
LibreNMS  | 1.61
DB Schema | 2020_02_10_223323_create_alert_location_map_table (159)
PHP       | 7.3.14
MySQL     | 10.2.31-MariaDB-1:10.2.31+maria~bionic
RRDTool   | 1.7.2
SNMP      | NET-SNMP 5.8

[OK]    Installed from the official Docker image; no Composer required
[OK]    Database connection successful
[OK]    Database schema correct
[FAIL]  Missing PHP extension: sockets
       Please install sockets
[WARN]  IPv6 is disabled on your server, you will not be able to add IPv6 devices.
[WARN]  Updates are managed through the official Docker image

custom Ios.php: https://p.libren.ms/view/a1e747ad#L95

we got the same issue with AeroHive AP120/121 Series.
Did you manage to find the root cause of the issue or prevent LibreNMS from deleting the sensors?

Unfortunately no, but it can be tied with sensor validation, or this is what I suppose.