RaspberryPi Zero loses connectivity

I have had a problem with RPI Zero. The system was working fine, and then it did not. I am using Raspbery Linux (Debian-based) with kernel 5.10.17+. Once a while (usually with network load) the system loses connectivity. Everything seems to be fine, if you have a serial/USB console there, but the wireless network fails. This problem was also mentioned here.

My workaround was to create a script with a cron scheduling. I have identified that the fault lies with the wlan driver, and it needs to get reloaded. So cron calls this script every minute, like this:

*/1 * * * * /usr/local/sbin/check_connection.sh

And the script (/usr/local/sbin/check_connection.sh) has this in it:

#!/bin/bash
# DST is the network gateway
DST=192.168.230.1
if ! ping -c 5 -t 5 $DST > /dev/null
then
  #/usr/sbin/reboot
  /usr/bin/logger "Restarting wlan0 network driver"
  /usr/sbin/rmmod brcmfmac && /usr/sbin/modprobe brcmfmac roamoff=1
fi

Set this script to be executable, and your RPI Zero should work just fine. This is not a solution, but a workaround, of course, but it works well.