Account does not show member of group, but cpanel does?

Account does not show member of group, but cpanel does?

Hello,

In the cpanel, I see a user listed under a group that I've created.

If I send email to the group email address, that user receives the email, which makes me think the user is actually a member of that group.

However when I log in as that user, the groups section of the their account page says that user is not a member of any groups.

How can that be, and which is correct?

Thanks,
Joe