Rg show Just once each item

Good morning
Iam creating a warehouse management and my database has a Lot of lines with the Fields date, material and quantity, so when i fill my RG tô show the sum of each item i got the result correct, but the cells in RG repeats.
How do i do to show Just once each item by name of material?
I tried to use :unique elements, and groupby but always hide ALL content when i do this setup.
Thanks for ALL.

Use Fixed Cells

How do i do this,
The customer Will input the item do the list, i cant put a static value

Draw a repeating group and keep it on 1 Row with image
So if one row’s value dont change (Keep Y/N to update list) add a button on the colum to change the values