After updating to WordPress 4.4, ACF is showing the title twice, even with “Seamless” mode turned on.
I see the field group name displayed above the first field of the group. As far as I know ACF has always shown then field group title. Is this what you mean?
Before WordPress 4.4, the group title would only display if you had “Style” set to “Metabox.” Now it displays for both “Seamless” and “Metabox”
I will mark this as a bug for the developer. You will probably get a quicker response if you submit a new ticket. http://support.advancedcustomfields.com/new-ticket/. This forum is pretty much just users helping users.