The flow is supposed to fail if it does not see any lookup value in excel. It's like Lookup in excel but in Flows and SharePoint List.
My flow:
Sample Fail:
Here's what I have in the Get a Row actions
Can you post screen shots of what you have inside of the Get a row actions?
You can handle the error using the "run after" feature, but I suspect that there is a better way to approach your issue. If you post screen shots, maybe I can offer some suggestions.