Update the parameter while using service principal with certificate

Hi,

I'm trying to update the dataset parameters using update parameter api. But i'm unable to do it:

below is the code mockup:

var credentialDetails = new UpdateDatasourceRequest();

var oAuthTokenData = new CredentialData
{
credentialData = new List<Credential>
{
new Credential { Name = "accessToken", Value =GetSQLAccessToken().Result.ToString()}
}
};
credentialDetails.CredentialDetails = new CredentialDetails
{
CredentialType = "OAuth2",
Credentials = JsonConvert.SerializeObject(oAuthTokenData),
EncryptedConnection = "Encrypted",
EncryptionAlgorithm = "None",
PrivacyLevel = "None"

};
var getDatasources = pbiClient.Datasets.GetDatasourcesInGroup(workspaceId, pbiReport.DatasetId);
var refreshRequested = new RefreshRequest
{
NotifyOption = NotifyOption.NoNotification
};
if (getDatasources.Value.Count > 0)
{

pbiClient.Datasets.TakeOver(workspaceId, pbiReport.DatasetId);
await pbiClient.Gateways.UpdateDatasourceAsync((Guid)getDatasources.Value[0].GatewayId, (Guid)getDatasources.Value[0].DatasourceId, credentialDetails);
await pbiClient.Datasets.UpdateParametersInGroupAsync(workspaceId, datasetIds.FirstOrDefault().ToString(), updateRequest);
await pbiClient.Datasets.RefreshDatasetAsync(workspaceId, datasetIds.FirstOrDefault().ToString(), refreshRequested);
}

how ever i'm unable to perform UpdateDatasourceAsync .Why i'm using this is because to refresh the dataset , i need to use this method  here i'm facing the issue and it returning the bad request. i'm using the SQL Acces token for the crendentials. Is there any way to update the parameter . please let us know