Hi
You need to create a custom code action to unmerge cells. I'm not sure if the latest version of excel vbo available on Blue prism has the action I think it has a merge action but maybe not a unmerge. I've provided the code below you need to create a new action in the excel vbo, add a code stage then add the following code:
Dim ws As Object
ws = GetWorksheet(Handle, Workbook, Worksheet)
ws.Activate()
ws.Range(Range).UnMerge
The inputs are Handle, Workbook and Worksheet. Hope this helps :)