Hi @KamilTee ,
Could you please share a screenshot of the configuration of your flow?
Have you created a flow as screenshot below:

The "Key value" field require a value of the Key column.
Please choose the "Key column" Value dynamic content in the "Key value" field.
Also please make sure the "Key value" would always be unique to find a corresponding row in the excel.
Best regards,
Community Support Team _ Alice Zhang
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