Permissions to access Linked In privatePlayableStreams - 500 or 403 error

Question

I have a next issue using Linked In API V2:

curl -X GET --header 'Accet: application/json' --header 'Authorization: Bearer <my token>' 'https://api.linkedin.com/v2/adCreativesV2/62119114?projection=(variables(data(com.linkedin.ads.TextAdCreativeVariables(vectorImage~:privatePlayableStreams))))' | json_pp
    {
        "variables" : {
        "data" : {
         "com.linkedin.ads.TextAdCreativeVariables" : {
            "vectorImage" : "urn:li:digitalmediaAsset:C560EAQFjbUgC1TlCcw",
            "vectorImage!" : {
               "message" : "URN Resolution failed for unknown reasons.: com.linkedin.restligateway.exceptions.GatewayAccessException: Not enough permissions to access: GET-playableStreams /assets/C560EAQFjbUgC1TlCcw/mediaArtifactPrivateUrls",
               "status" : 500
            }
         }
      }
   }
}

My application have r_basicprofile, r_ad_campaigns permission scopes.
My user has 'account_manager' level access.

I'm not sure which permissions do I need to access vectorImage's Playable Streams?

Here in Asset Playable Streams Table section https://developer.linkedin.com/docs/ref/v2/digital-media-asset they write about authorizationMethod and my understanding is that only assets with authorizationMethod = PUBLIC are available to access, may be my problem is not in scopes?

I'll appreciate any information on this issue. Thanks!