Missing Labels

I have FORM with several fields. All fields are missing labels. I tried to update them manually and for some time it was OK, until I did Sync with dictionary. They are all gone again. I checked Lanuage file and all is OK, I also run Theme, Localization updater but it did not help. I updated Dictionary from the database overriding existing language files, but no luck. Cleared browser Cache, Cookies - no luck
When I go to Dictionary and click EDIT for the particular table linked to the form all Labels are blank.

Any ideas what can cause this ?

Arthur

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