Power Bi Embedded RLS with REST API

We are creating new Reports via the embedd API of PowerBI Premium with RLS. For embedding in VIEW and EDIT mode the provided EffectiveIdentity works well. But when it comes to accessLevel CREATE we get "Forbidden" response.

var requestParameters = new GenerateTokenRequest(
	"create",
	datasetId,
	allowSaveAs: false
	identities: new List<EffectiveIdentity> { new EffectiveIdentity(UserId, roles: ["Role1"], datasets: new List<string> { datasetId }) }
);

Is RLS supported in CREATE mode? When yes, how can we get a token with correct RLS settings?