I ate Kobe Beef Hotpot...... :)

Did you see the certificate? If you didn't, it was almost definitely not Kobe beef. And FYI -- "Wagyu" is a made-up marketing term that just means "Japanese beef/cow," but is not regulated by any law to ensure that the cows are any specific breed or even raised in Japan -- except in Japan itself. That is the handy thing about using foreign language words this way. They have no concrete legal meaning and you can't even ultimately claim any false advertising was involved since they can easily argue that they didn't actually make any intentionally misleading claims.

This is akin to selling American white sparkling wine as French champagne and using some misused French word to do it, or any other false use of a regional trademark reputation, and it is incredibly widespread in places that don't regulate use of those terms by law -- in particular the US, which I'm guessing is where you had this, as that is the only country I have visited where this misuse of "Wagyu" as a scam synonym for Kobe beef has become industry standard.

Forbes has a couple of great articles on it, and as much of a bummer as it can be to be disabused of a fantasy and discover you have been swindled, I suggest you check it out.

If you saw the certificate though, awesome! Must have cost a pretty penny.