I am still not clear on the series of events.
I did the following:
1. Created a graph in Excel. The graph was shown as Chart 1 (hold Ctrl key down and right-click on Chart and see the name above cell A1)
2. Copied the graph to PPT using Paste-Link
3. In Excel I copied the graph and pasted it into the same worksheet. The graph is shown as Chart 2
4. I changed the series in Chart 2 to a new set of data, but all the rest is identical, titles, axis labels colors etc.
5. I copied Chart 2 and pasted it into a new slide in PPT using Paste-Link.
Looking at the 2 slides in PPT, both charts look the same (chart type, titles, colors), but show different data.
Back in Excel I updated data in a series used in Chart 1 and data in a series used in Chart 2.
In PPT both charts showed the new (different) data.
I then updated the data for Chart 2 but left the data for Chart 1 the same.
In PPT Chart 2 showed the updated data and Chart 1 was unchanged
In PPT Menu - Edit - Links - there are two links showing - both to the same Workbook & Worksheet, one ending in Chart 1 and the other ending in Chart 2
This sequence of events works as expected.
Can you identify what you did differently.