Can't open diamond jack

As the title suggests, I can’t open any diamond jacks. Maybe it’s my misunderstand, but I’m under the impression that once you open 8 surrounding jacks, the game should allow you to open the diamond jack.

This does not happen for me:

After opening all jacks the I get the following message when tapping the diamond jack:

Hellooo! @Wickersham. Sorry for the late response.

After opening all the normal jacks you will unlock the diamond jack.
But just like normal Jacks, you have to get XP to be able to open it.

Like a normal jack, You have to complete that getting XP.