Occasional Contributor

I have created a list from Excel, and I am trying to calculate the date difference in a column, I was able to create the formula in excel, however when I created the list in Teams, my formula no longer works, so I tried to use the formula from Support.office.com, however that formula doesn't work as well.  How do I calculate the date difference?  I used this formula =DATEDIF([Column1], [Column2],"d")

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