Sigh - just search.
9x21 is a round for countries where civilians can't own military rounds - ones used by the armed forces.
You can get Glocks chambered in it.
See, very easy to find out. Given the gun is Italian - that probably explains it.
Doubtful someone in the USA not truly being expert would know that. Or someone who can use the Google.
No need to panic.
Doubtful the gun would come here. Would it chamber a standard 9mmx19? Don't know that.