tvtime-command: command not found

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:

/usr/bin/tvtime-command - from package: tvtime

You may install the required package with command apt-get install {package}

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