pivot table - unable to add calculated item - Excel says it's grouped but why?

Hi all,

I want to understand why Excel consideres a pivot table grouped and how this could be resolved?

So I have a table with 10 columns, and I want to make a pivot table where only 3 cols are affected. Highlighted with blue, cols D, G and H.

Here is my pivot:

- columns D and G as rows

- H as values

Now if I want to add a calculated field, say, the ratio of "víz" and "limonádé", it tells me that I can not do that because the Pivot Table report field is grouped.

Now if I simply copy-paste only these columns to a separate ranges and create the very same pivot table from this, Excel has no problems with creating the calculated item.

So why can I add calculated Item from the second, and why can't I add a calculated item from the first table? I obviously did not add a manual grouping, it is just putting multiple fields into the Rows.

Thank you for your explanation!

sample files attached:

sample - pivot item issue - 0.xlsx --> I created some pivot tables before this one, I deleted everything not needed. I tried to rebuild the cash, did not work.

sample - pivot item issue - success.xlsx --> I made a copy of the data sheet itself, and I wanted to make a pivot to reproduce the issue - and I failed... I can create a calculated item here. Hm...