Expression result not same

[reggieneo]

Hi All,
I have used this:"Filter(Sales Summary,[Timestamp]=MAX(Sales Summary[Timestamp])) " in my reference rows from my action. it is working as expected.

I have copied the same expression in a similar app and it is strangely returning list instead of one Max Value.
I looked at the g sheet and manually inputted a spreadsheet formula to determine the Max Value. so I am sure the expression should give me the max but instead, it gives me a list.

what I am missing here?

thanks.