ChangeTierInput Class

public void changeTierTest(){
   //...Create a list with LoyaltyManagement.ChangeTierInput as a datatype
   List<LoyaltyManagement.ChangeTierInput> changeTierList = new List<LoyaltyManagement.ChangeTierInput>();

   //...Create an instance of the list object and set the input values 
   changeTierList.add(new LoyaltyManagement.ChangeTierInputBuilder()
      .setLoyaltyProgramMemberId('0lcxx00006000001AAA')
      .setProgramName('baProgram')
      .setTierGroupName('QualifyingGroup')
      .setTargetTierName('Gold')
      .setChangeReason('Reason for change.')
      .build());

   //...Pass the list that contains the input values to the LoyaltyResources.changeTier() function.
   //...Store the output returned by the function in the ChangeTierOutput object
   List<LoyaltyManagement.ChangeTierOutput> changeTierActionResults = LoyaltyManagement.LoyaltyResources.changeTier(changeTierList);
   System.debug('Change Tier Successful Operation:'+ changeTierActionResults.get(0).isSuccess());
}