So, it looks like the snipe didn't go through for some reason and AS might have got the reason wrong. I'd log a fault call via the HELP tab and, if nothing else, they might give you some free snipes!
As a check - try a manual bid followed by an immediate retraction on one of this guy's auctions - if it accepts it then I guess it means you're not banned after all! [Don't bid too high on something tacky just in case it goes wrong and you win!].
R2