Hi @PietroFarias ,
Could you please share more details about your scenario? Do you have another list which includes Category column and Subcategory column? Then would you like to make the category dropdown automatically populate with the corresponding category after subcategory is selected? What column types are the two columns, Choices or LookUp?
Assuming that category is a Choices type column and Subcategory is a LookUp type column in current SP list, and a Text type Subcategory column and a Choices Type Category column, since you use a LookUp to auto populate a corresponding category in the dropdown, you will need to modify the Update property of Category Data Card to:
LookUp(Choices(ListName.Category),Value = CategoryDropdown.Selected.Value)
Below is a test on my end:.
1\ List 1 includes Text column and Choices column, list2 includes LookUp column and Choices column:


2\ DefaultSelectItems of Combo box of Choices column is set to below formula and DisplayMode set to Disabled:
LookUp(list1,Title1 = DataCardValue2.Selected.Value).TestColumn
3\ Update of the data card which includes the disabled combo box is set to:
LookUp(Choices(List2.Test123),Value = DataCardValue1.Selected.Value)
Hope this helps.
Best regards,
Community Support Team _ Jeffer Ni
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