Board Thread:Questions and Answers/@comment-8862617-20130504165922/@comment-8911049-20130504184827

Like the individual above pointed out, NO ONE can be attacked by anyone 10 levels higher (simply because it's not really fair in a sense), BUT this rule only apply if your level 80 and lower, once you hit level 81+ the rule no longer applies and you can be attack by anyone.

And you will not get the sealstone if you lose against someone.

So it's not a glitch you just have to be mindful of the person your attacking because you will lose no matter how strong you are if they are 10 levels lower than you.