Too many unique values in Pivot, but same works with Group By node

Groouping on the sam columns and counting unique id-s works with Group By but gives this in Pivot:

​Skipped group(s): ad_id groups: "bump" cause: "Group contains too many unique values"

The unique values per group are way below 10,000 which is the limit.

Hi manu5,

Could you please post an example of your workflow?