Hi @SRMHD ,
So you will "Get items" from your destination SharePoint list and "List rows present in a table" from Excel.
Then you put a Condition to tell whether "Get items" outputs are empty.
If yes, add a new item into destination Sharepoint list, which works fine.

If not, which means the destination list has items existed, you "Get items" from destination Sharepoint list again and "Update items" with dynamic content from Excel action.

Correct me if I make any misunderstandings to your flow process.
Here are more questions to narrow down your issue:
1. The dynamic contents of "Value"/"ID" originate from which action? I mean which "Get items"? the first one or the second one?
2. In your newly posted snap, I notice the dynamic contents you feed to the "Update items" were changed to Sharepoint ones. However, in "If no" branch, the outputs of Sharepoint "Get items" should be empty right?

As you only share parts of your flow, it's hard to understand it as a whole. Could you please share the complete process and give it an introduction if we still miss the point this time?
Community Support Team _ Wenjuan Zou
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