[NRK] Improve extractor
diff --git a/yt_dlp/extractor/nrk.py b/yt_dlp/extractor/nrk.py
index 4d723e88688..0cf26d5981f 100644
--- a/yt_dlp/extractor/nrk.py
+++ b/yt_dlp/extractor/nrk.py
@@ -13,6 +13,7 @@
     ExtractorError,
     int_or_none,
     parse_duration,
+    parse_iso8601,
     str_or_none,
     try_get,
     urljoin,
@@ -247,6 +248,7 @@ def call_playback_api(item, query=None):
             'age_limit': age_limit,
             'formats': formats,
             'subtitles': subtitles,
+            'timestamp': parse_iso8601(try_get(manifest, lambda x: x['availability']['onDemand']['from'], str))
         }
 
         if is_series:
@@ -797,7 +799,7 @@ def _real_extract(self, url):
             for video_id in re.findall(self._ITEM_RE, webpage)
         ]
 
-        playlist_title = self. _extract_title(webpage)
+        playlist_title = self._extract_title(webpage)
         playlist_description = self._extract_description(webpage)
 
         return self.playlist_result(

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### Description of your *pull request* and other information

Close #3211