"Request Authorization Tenant Mismatch" when creating Teams Call and notification is not working?

Question

I am using Microsoft graph API "https://graph.microsoft.com/beta/communications/calls" to make calls to teams but it gives me tenant error as per multiple answer available here I tried to pass the tenantid in the request but it does not work. I am using the new API version and basic example for create call.

Below is the code example I am using.

const client = await getApplicationClient(accessToken);
    const call = {
        '@odata.type': '#microsoft.graph.call',
        callbackUri: 'https://api.helpaas.com/v1/api/users/handleCallCallback',
        //   },
        targets: [
          {
            '@odata.type': '#microsoft.graph.invitationParticipantInfo',
            identity: {
              '@odata.type': '#microsoft.graph.identitySet',
              user: {
                '@odata.type': '#microsoft.graph.identity',
                    id: id.AAD_UserGuid, // sending from azure user object
                    displayName : id.DisplayName,
                    "tenantId" : "<subcription tenant_id>",
              }
            }
          }
        ],
        requestedModalities: [
          'audio'
        ],
        "allowConversationWithoutHost": true,
        mediaConfig: {
          '@odata.type': '#microsoft.graph.serviceHostedMediaConfig',   
        },
        "tenantId" : "<subcription tenant_id>",
        "toneInfo": {
            "@odata.type": "#microsoft.graph.toneInfo",
            "sequenceId": 1024,
            "tone": "tone0" }
      };
    const response = client.api(`/communications/calls`)
    .post(call);

Also Please explain

1. When call is made notification pops-up in Teams Web but with teams app its not working How to fix that?
2. What is the difference between "serviceHostedMediaConfig" and "appHostedMediaConfig" and how to choose between them?