Highlighting and underlining is not working anymore!
This is most likely because you upgraded your device to iOS 9.
There was an important announcement made about this issue a number of days before iOS 9 was released. You can find the announcement here: http://support.equipd.me/entries/83891695-Annotations-broken-on-iOS-9-and-9-1
Please do not email me about this topic - just keep an eye on the forums for future updates.