Hello, you do not need to use both the Item Name and Index Values. I suggest you try getting it to work just using the Item Name (because the index location of an item could change if items were added or removed from the list in future).
Also, best practice would be to read all items, loop through the collection of all items until you get to the one you want (using an InStr comparison), and then selecting the item based upon name only - using the full text of the found item. Throw an exception if the item is not found. This will make your solution more robust - as you are using the actual values in the combo which will cater better for extra spaces etc after the text that you might not know about.
If in doubt I suggest you contact a more experienced lead developer within your organisation or your Blue Prism DEM for more details about this.