Unit of measure issue in Product Category Units Quota Planning

Hi experts,

My client needs to maintain quota for salespersons based on R/3 product hierarchy level. (1000 kg of Product Hierarchy Level 01234 per month, 2000 KG of Product Hierarchy Level 56789 per month, vs.). R3PRODHIER is the category assigned to Sales application.

So in Quota Planning, sub-assignment block Product Category Units, I want to maintain quotas. I press Add button, mark the Hierarchy level I'd like to plan quota to, and press Choose button, but "Unit of Measure" field does not fill up. Surprisingly, in the dropdown list, there is not an option which I can select (i.e. 'KG'). The list is empty, even after I fill Q1, Q2, Q3 and Q4 values. So, I am not able to use the quota planning functionality.

Any ideas why this is happening and how to fix it?

Thanks for your time,