What was this "Meso Glitch" (Dupe?) again?

I don't suppose you could give me more information than that. For example, about what % of people ran into this? How long were their bans? Do hell bans still happen? What specifically caused the ban?

Whoops, sorry for being vague; I'm not entirely sure, but they basically hellbanned players for being in posession of duped mesos, which included those who received mesos from people buying their things in their shops. I really don't remember how long this all lasted but it affected a large amount of players. Hellbans haven't happened again since then, other than the accidental hellbannings from last month.

This doesn't really explain why you were actually banned, though, since hellbans aren't actual bans, but just blocking people from trading/buying/selling/dropping items.