I tried to make a Visio flowchart connected to an Excel workbook. It worked up to a point. When I used a Decision shape with two next steps, I got an error.

I got that error even though I used the Microsoft template "Visio Data Visualizer – Cross-Functional Flowchart Process Map.xlsx" and the values in the support article, https://support.office.com/en-us/article/create-a-data-visualizer-diagram-17211b46-d144-4ca2-9ea7-b0f48f0ae0a6?#ID0EBAFAAA=Next\_ID
I also got that error when I tried different values, such as letters for step IDs, or a space after the comma (4, 5), or a semicolon instead of a comma (4;5).
(The error said, Diagram Refresh Failed: Some of the values in the column 'Next Step ID' don't refer to values in the column 'Process Step ID'.
The following values in the 'Next Step ID' column are missing from the 'Process Step ID' column. Note: Ensure that you are using the correct delimiter to separate multiple values. Open the workbook to edit the data, save your changes, and then Refresh
the diagram again.)