This error is visible when you print hand records, report score recaps, or publish internet reports. If so, hands on the even-numbered boards are not shown, and hand 2 is shown together with board 3, hand 3 together with board 5, and so on.
If you import PBN files from a non-upgraded Dealer4, you can get this problem. This is an issue that was resolved already in version 4.7, April 2017, or at least explained in that version.
The change log from that version included the following section:
DUPLICATION – DEALER
There is a duplication machine called Dealer4. It can, among other things, export PBN files that can be imported in Magic Contest.
In the previous Dealer4 version (4.42) an error was introduced leading to the PBN export being wrong. This lead to strange things in Magic Contest. Dealer4 has dealt with this in the latest version (4.50) that you can download from their website.