Hi @alex5p ,
What is the type of columns that save each items? What is the items property of listbox?
The final formulas is up to the column type of SP list. However i have made a test, you can refer to my example(just 4 items).
1. create 4 single-text columns for SP list, named T1, T2, T3, T4.
2. set the items property of list box as below, the 4 list items are "A","B","C","D", and append to ID for each items for convenience of lookup.
Table({Value:"A",ID:1},{Value:"B",ID:2},{Value:"C",ID:3},{Value:"D",ID:4})3. set the following formula to button OnSelect, each column corresponds to each item. e.g. T1 column corresponds to the value that ID=1.
ClearCollect(col,ListBox1.SelectedItems);Patch('SP list',Defaults('SP list'),{Title:"Test-1",T1:LookUp(col,ID=1,Value),T2:LookUp(col,ID=2,Value),T3:LookUp(col,ID=3,Value),T4:LookUp(col,ID=4,Value)})

Hope this can help.
Best regards,
Sik
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