2nd Y Axis not working

Hey all,

I am an absolute newbie to Grafana but totally love the way it works. My current Dashboard (I startet with Grafany only yesterday) looks like:

Currently I am struggling with 2nd Y Axes. I go the Override way but either the whole Y-Axis changes from left to right or it is not shown at all.
I was reading quite a lot tutorials in the web, but still cannot figure it out. Here Learn Grafana: How to use dual axis graphs | Grafana Labs the author says

  1. In the Colors pop-up, click the Y-Axis tab, and enable Use right y-axis.

But I don’t have an Y-Axis tab. This is what I tried (Override 4), but no right Y-Axis:

Anyone with a pointer for me? Thanks already now!

Update: this is working now with another item with a different unit. Is this only working with different units?