Tools required:
adjustable wrench
If none of the connection points are broken and the steam knob spins with the brass valve in the center the internal steam valve is likely compromised and needs to be replaced.
LUCCA A53 / Vivaldi: Steam Wand Not Closing
Below are photo instructions for what to check if your La Spaziale LUCCA A53 or Vivaldi espresso machine steam wand won't close.