How to start and pause Power BI Embeded service through REST API calls using ASP .NET application

Dear All,

I need to start and pause Power BI Embeded service through REST API calls using ASP .NET application,

I used below code but i get following error while executing : Authentication failed. The 'Authorization' header is missing

Start:

string requestUri = "https://management.azure.com/subscriptions/{Enter subscriptionId}/resourceGroups/{Enter resourceGroupName}/providers/Microsoft.PowerBIDedicated/capacities/{Enter dedicatedCapacityName}/resume?api-version=2017-01-01-preview";

HttpWebRequest request = System.Net.WebRequest.Create(requestUri) as System.Net.HttpWebRequest;

            request.Method = “POST”;

            request.ContentLength = 0;

            request.Headers.Add("Authorization", String.Format("Bearer {0}", accessToken));

HttpWebResponse response = request.GetResponse() as HttpWebResponse;