diff --git a/assets/base/i18n/pl.json b/assets/base/i18n/pl.json
index 317c28f10..f54dae044 100644
--- a/assets/base/i18n/pl.json
+++ b/assets/base/i18n/pl.json
@@ -291,6 +291,7 @@
   "custom_status.suggestions.recent_title": "Ostatnie",
   "custom_status.suggestions.title": "Propozycje",
   "custom_status.suggestions.working_from_home": "Praca zdalna",
+  "date.unknown": "Nieznany",
   "date_separator.today": "Dzisiaj",
   "date_separator.yesterday": "Wczoraj",
   "default_skin_tone": "Domyślny odcień wyglądu",