diff --git a/src/NodaTimeAutotranslater.php b/src/NodaTimeAutotranslater.php
index cea4838..57a4680 100644
--- a/src/NodaTimeAutotranslater.php
+++ b/src/NodaTimeAutotranslater.php
@@ -504,8 +504,11 @@ final class NodaTimeAutotranslater {
             $output = [];
             $cases = NodaTimeAutotranslaterLocales::cases();
             foreach ($cases as $tLang) {
-                $start_term = self::getTranslations($startTimeInfo)[$tLang->name];
-                $end_term = self::getTranslations($endTimeInfo)[$tLang->name];
+                $startTls = self::getTranslations($startTimeInfo);
+                $endTls = self::getTranslations($endTimeInfo);
+                if (empty($startTls) || empty($endTls)) return [];
+                $start_term = $startTls[$tLang->name];
+                $end_term = $endTls[$tLang->name];
 
                 $output[$tLang->name] = \sprintf($tLang->formatYearspanForSprintf(), $start_term, $end_term);
             }