How to automate an alert when duplicate row is created

[Jean_Pierre_Traets]

Dear @Koen73

Just to keep it simple.
This post explains how to find duplicates:

Highlight duplicates in a column using a conditional format

Quick little conditional format that I often use to find the duplicates in a table - [38%20PM] The formula I have used here is Table.Filter(Column.Contains(thisrow.Column).Count() >1