Hi @AhmetOz,
Have you solved your problem?
Do you want to display the default selected item within the Combo Box when you edit the item?
Could you please tell me how you set the Items property of these Combo Boxes?
Since you have excel table as your data source, I just assume that you populate the Combo Box with General columns, if you set the Combo Box Items property as Table1.ColumnName or Distinct(Table1,ColumnName), please set the DefaultSelectedItems property of the Combo Box as below:
[Gallery.Selected.ColumnName]
Note that if you have a Combo Box, you should set the DefaultSelectedItems property where expects a table value.