Issue in setting a Function in Response


In the response i am getting a value that needs to be exactly same what i am sending in the request. Now i am trying to set that value as function (i.e- copy from or substring) . When i am selecting particular function in the response for a particular value then all of the remaining values are also changed to what i did for the single one. Here i need to have the function for a particular value only and not for the other values. Kindly suggest me here to provide a solution.