If a comment flag is the first flag a user has on a site, then even if that flag is marked helpful, it will not show up on the flag summary page.
As soon as an another valid (non-comment) flag is accepted, the flag count on the right will update to show that there are now two valid flags, one comment, and one post.
While I understand that this is accepted behavior, it is pretty confusing, and should change.
(1) helpful flags
but it won't show anything in the flag review. Try flagging an actual post (this one would work for a test) and see what happens.