Timeslots/box and whisker

Hello,

I am working on a box/whisker-chart with random timeslots between 08:00-11:30 during the workdays.

When I enter a timeslot before 09:30, it completely alters the looks of the actual chart.

Here is what I want it to look like (with a few altered timeslots, so there is none before 09:30)

Chart 1.png

Here is what it looks like when I have the correct timeslots - it shows timeslots from 00:00-12.00 instead of the timeslots that is actually in use.

chart 2.png

What might the problem of that be/how can I solve it without altering with the timeslots?