I see this topic is quite old but I had this problem as well. Perhaps adding it here will help others find it more easily. My hubpiwi stopped working when I upgraded my raspberry pi zero (no W) with the hubwipi to raspbian bulleye. The thing I finally stumbled on to was to add wext to the wpa_supplicant options. Here are the details with thanks to those who wrote this up:

https://www.linuxbabe.com/debian/connect-to-wi-fi-from-terminal-on-debian-wpa-supplicant

The following is needed for hubwipi using rtl8188EUS
lsusb ->
ID 0bda:8179 Realtek Semiconductor Corp. RTL8188EUS 802.11n Wireless Network Adapter

You can get the wifi working from the command line using this:

sudo wpa_supplicant -B -D wext -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant.conf

Unfortunately, it will be gone after a reboot. To get it to start at boot time see (with my thanks here as well)

https://superuser.com/questions/1434621/set-wpa-supplicant-default-driver-on-startup

Here is what worked for me: To the end of the file /etc/dhcpcd.conf. add:

interface wlan0 env ifwireless=1 env wpa_supplicant_driver=wext

Your interface name may be different from wlan0. Running the command

ip addr

will tell you the name.

I have tried this on other raspberry pi zero w's and adding the "wext" did not seem to bother them. I did not do too much testing here so I only add the wext when I need it.

One of the notes I saw warned that the network speed of the rtl8188eus was low and I experienced this as well but it was sufficient for my purpose and let me update the OS on the rpi zero with the hubwipi.

I hope this helps someone searching for how to get the hubwifi to work again with a newer Raspian OS release.

Have you set the Country from raspi-config before configuring Wi-Fi ? If hubpiwi requires an additional Wi-Fi driver, then maybe you need to install it before configuring the Wi-Fi.