Unable to get some Facebook Ad API fields

Question

I am trying to get the Video fields, but API is not returning the columns even API requesting in fields.

Fields I'm trying to get are: video_p25_watched_actions,video_p50_watched_actions,video_p75_watched_actions,video_p100_watched_actions.

My API request parameters as below:

request.AddParameter("export_columns", "['actions:video_view','actions:video_view:video_p25_watched_actions','adgroup_name','date_start','date_stop','campaign_group_name','campaign_name','adgroup_id','impressions','clicks','spend','actions:like','actions:offsite_conversion','actions:receive_offer','actions:rsvp','actions:leadgen.other','actions:link_click','actions:comment','actions:post','actions:post_engagement','social_impressions']");
request.AddParameter("fields", "['ad_name','campaign_name','adset_name','ad_id','impressions','clicks','spend','actions','social_impressions','video_p25_watched_actions','video_p50_watched_actions','video_p75_watched_actions','video_p100_watched_actions']");
            request.AddParameter("filtering", "[{ 'field':'ad.impressions','operator':'GREATER_THAN','value':0}]");

Please help me if I am missing anything.