Hi @CarlHRVA ,
Do you want to filter a gllery based on the selection of a data table?
If so, please try this formula: (set the gallery's Items)
Filter(tablename, 'CUSTOMER_x0020_NAME'=DataTable1.Selected.'CUSTOMER NAME')
Since ManagerUIGallery.AllItems can not represent a data source, you can not filter a gallery's Items based on the items in the gallery.
It is a kind of circulation.
And your collection is the aggregate data, so I suggest you filter the data source directly.
What's more, you can not compare two column directly like your formula:"CUSTOMER_x0020_NAME"='CUSTOMER NAME'.
You need to compare one column with a value. DataTable1.Selected.'CUSTOMER NAME' represents the customer name that you select in the datatable.
Best regards,