hmm, I do wifi connect in bash/xterm

one shot
sudo vi /etc/network/interfaces
add

source /etc/network/interfaces.d/*.cfg

if not already there

make sure /etc/network/interfaces.d folder exists

later, check what is available

sudo iwlist wlan0 scanning |grep -e ESSID -e Quality
                    Quality=70/70  Signal level=-40 dBm
                    ESSID:"apn 1"

If never used one before

sudo /etc/network/interfaces.d/apn_1.cfg

iface apn_1 inet dhcp
    wpa-ssid "apn 1"
    wpa-psk mypass1234

from now on to connect to "apn 1" I just do

sudo ifup wlan0=apn_1


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regards
piotr