isImport Server Side API is not working

Good Day, I'm currently developing validation triggers that will exclusively run during import only, I'm using the "isImport" server side API which i already used in my previous application, but recently i noticed that the api is not working properly as it supposed to return "true" during import but it still return "false" even during the import process. I've attached some screen shots to provide more info and i've tested there to print the returned value of the api via validate record trigger. I Apologize for this sudden issue Many Thanks Ruben Guico Rollbase PH