In PBA 5.5.5 a new feature "Promotion Validation" was implemented. The words 'apply' and 'reset' that appeared since then are not localized, when the customer is logged in under language different from English:
The translation is missing in the locale files, the bug POALP-882 has been created to add the translation to the locale files shipped by Parallels.
The bug is fixed in PBA 5.5.7 - proper localization was added. If update is not possible at the moment, add the required translation to the dictionary volume manually, the steps are described in the article #116938, steps 1-3 of the resolution part.