[Закрытые] Translations keep resetting updating translations

Background of the issue:
I am trying to update some translations in the back-end via the string translations. For some unknown reason, some translations fall back to a previous translation. This issue is especially problematic with links and shortcodes to forms. I usually notice it changing back when saving a page/post or other translation. Link to a page where the issue can be seen: скрытая ссылка

Symptoms:
The 'kontaktformular' button at 'Kunden-geschichten' should go to скрытая ссылка, but it instead directs to скрытая ссылка. The link changes back to the wrong page and wrong language after I update it.

Questions:
Is this a familiar issue?
How can we fix it?