Line chart: cannot insert field into Y2

Hello all,

I have the following data structure

Stock is the number of items of that product I had in my storage on that given day 

MinimumStock is the minimum number of that item to trigger the order

Date in my example table is dd/mm/yyyy, just to clarify.

The real table I'm using has about 300k rows, and more than 1k products.

I would like to get something like this:

In this way, when i filter for a single product, I get his storage movements and his minimum stock, and I can compare them.

In PowerBI, I got a line chart with

Axis: Data

Legend: ProductID

Value: Stock

If I try to add MinimumStock to Y2, nothing happens. Like I drag the column over the Y2 box, it gets dashed, I drop it and nothing, it does not get added to the Y2 box or the chart.

If I just check the column name, it goes into the tooltips, but that's not what I want.

Any suggestion? Even if I manually add this simple example data to my PowerBI model, it behaves in the same way.

Thank you very much!

Fabio