it literally means just that. Sometimes if you're trying to trade or drop mesos that you don't have in your inventory it will auto ban you for this reason. It might not have been your intent to try and trade more mesos than you had (usually while your client is lagging) and in that case you would have to make a ban appeal and hopefully you will be unbanned like this guy > https://royals.ms/forum/threads/ban-appeal-attempting-to-trade-more-mesos.73546/