wdctl: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/bin/wdctl - from package: util-linux

You may install the required package with command apt-get install {package}
Error in other languages:
wdctl: bevel nie gevind nie
wdctl: comandă negăsită
wdctl: comando não encontrado
wdctl: commande introuvable
wdctl: command not found
wdctl: käsku ei ole
wdctl: không tìm thấy lệnh
wdctl: komanda nerasta
wdctl: Kommando nicht gefunden.
wdctl: kommandot finns inte
wdctl: komut yok
wdctl: nie znaleziono polecenia
wdctl: níor aimsíodh an t-ordú
wdctl: no se encontró la orden
wdctl: no s'ha trobat l'ordre
wdctl: opdracht niet gevonden
wdctl: parancs nem található
wdctl: perintah tidak ditemukan
wdctl: príkaz nenájdený
wdctl: příkaz nenalezen
wdctl: команда не найдена
wdctl: командата не е открита
wdctl: 命令找不到
wdctl: コマンドが見つかりません