To edit response code:
  1. Navigate to Marketing and Communications>Response categories and responses
  2. Click on Response category
  3. Click drop down next to response and select Edit
  4. Update response and/or code
  5. Save

To add response code:
  1. Navigate to Marketing and Communications>Response categories and responses
  2. Click on Response category
  3. Click drop down next to response and select Edit
  4. Add response and code
  5. ​Save