curl --request POST \
  --url https://api.sandbox.asapp.com/metadata-ingestion/v1/many-customer-metadata \
  --header 'Content-Type: application/json' \
  --header 'asapp-api-id: <api-key>' \
  --header 'asapp-api-secret: <api-key>' \
  --data '{
  "items": [
    {
      "externalConversationId": "id-509",
      "externalCustomerId": "555.555.0100-jdoe@example.com",
      "eventId": "eventId-1938",
      "status": "new",
      "phoneNumber": "(555)555-0100",
      "emailAddress": "jdoe@example.com",
      "userId": "user908038",
      "addressCountry": "United-States",
      "addressState": "New-York",
      "addressZipcode": "10001",
      "attributes": [
        {
          "name": "attr1_name",
          "value": "attr1_value"
        },
        {
          "name": "attr2_name",
          "value": "attr2_value"
        }
      ]
    },
    {
      "externalConversationId": "id-203",
      "externalCustomerId": "555.555.0101-mdoe@example.com",
      "eventId": "eventId-1331",
      "status": "existing",
      "phoneNumber": "(555)555-0101",
      "emailAddress": "mdoe@example.com",
      "userId": "user3201033",
      "addressCountry": "United-States",
      "addressState": "New-York",
      "addressZipcode": "10002",
      "attributes": [
        {
          "name": "attr1_name",
          "value": "attr1_value"
        },
        {
          "name": "attr2_name",
          "value": "attr2_value"
        }
      ]
    },
    {
      "externalConversationId": "id-69221",
      "externalCustomerId": "555.555.0191",
      "attributes": null
    },
    {
      "externalConversationId": "id-69223",
      "externalCustomerId": "555.555.0193"
    },
    {
      "externalConversationId": "id-69229",
      "externalCustomerId": "zdoe@example.com",
      "phoneNumber": null,
      "userId": null,
      "addressCountry": null
    }
  ]
}'