Try this formula in place of your current T/F
IIF(LEN([Customer Name 1]) = 0,FALSE,CONTAINS([Customer Name],[Customer Name 1]))
IIF(LEN([Customer Name 2]) = 0,FALSE, CONTAINS([Customer Name],[Customer Name 2]))
I've changed the name of your parameters to make my life easier. You also do not need two fields for customer name. Making a copy in this case is pointless as they are identical. You can have two functions looking at the same field. What this calc does is return false instead of true whenever then custom parameter is empty. LEN() is a function that returns how many characters there are in a string. When its 0 then its empty. And when its empty you now get a false. When you get a false then that condition won't be true for all the other names.
Hey Carl !
Thanks for your answer, Is there a possibility to show all the customer name by default when the the parameters are NULL?
I want to display all customer names by default and when users filters it should apply accordling.