I recently had this problem but what fixed it for me was
Sudo apt-get install - - reinstall network-manager
I hope this helps,
Some useful commands I've learned along this journey are
// lspci / displays pci //
Lsusb / ports //
Netstat - I /network services //
Ip link show / can display your wlan0 card if not detected by ifconfig
// Lspci also helps //
Rfkill show all / my laptop had a "hard block" button that had an override over my wlan0, pressing ctrl c fixed this for me //
Iwconfig / was used to check the status of my wlan0 card //
Airmon-ng / showed my wlan0 card type as I originally thought it was a driver issue //
Dhclient wlan0 / started a dhcp client as to try to resume connectivity //
//WL-
ifconfigis obsolete now (no longer installed), maybe you could update this to useip link set wlo1 downetc. This would also get around the problem that your edit made this answer extremely similar to velix's (although I think thesudos in your version are needed). – Zanna Sep 07 '20 at 16:37