Lastet payment date

[Stella Ei]

I want to know the latest payment date based on the criteria(customer code).

I am now using this formula

=MAX(IF(Table5[Customer Code]=C5,Table5[Payment Date]))

and also CSE.
Customer code Latest Payment
C5 I5
C6 I6


only the first cell shows the correct date. I copied it down the I coulmn and the date shows only 1/0/1900. Help me plz.