WPML String Translation not working

I try to translate the frontend labels with wpml string translation like the documentation sais, but with no effect. The labels in admin area are changing but not in frontend templates.
https://wpstorelocator.co/document/translations/

i also created the .po and .mo files but doesnt work either.

i cleared the transient cache with no effect.

What else can i do or ist translation broken?

using versions:
wordpress 4.3.1
wpml 3.3.3
string translation 2.3.4
wp store locator 2.0.4
php 5.5.29

https://www.ads-software.com/plugins/wp-store-locator/