Translation not showing for field labels on registration screen

Hi Tuan. I'm having a problem with Event Booking. I have an event in Spanish here matthewsenvironmentalsolutions.com/esp/c...tions.com/esp/coc-mx

The translation is working perfectly for most of the fields, but it's not working properly for a few on the Individual and Group registration pages. Even though translations are loaded for the elements of First Name, Last Name, Organization, etc. the translated values are not appearing on the front end. A screen cap is attached. What can I do about this?

Thanks
Paul