Getting Authentication Error 401 with OpenTelemetry traces ingest

[sj]

I am trying to export OTLP trace data to Dyantace using OTLP collector with the following configuration. The collector request fails with  HTTP status code 401. 

2021-08-19T08:20:46.518-0400 info exporterhelper/queued_retry.go:316 Exporting failed. Will retry the request after interval. {"kind": "exporter", "name": "otlphttp", "error": "error exporting items, request to https://xxxxx.live.dynatrace.com/api/v2/otlp/v1/traces/v1/traces responded with HTTP Status Code 401", "interval": "4.118644073s"}

I am following the steps give at https://www.dynatrace.com/support/help/how-to-use-dynatrace/transactions-and-services/purepath-distr...

 Following is my OpenTelemetry collector exporter configuration:

exporters:

     otlphttp:

       endpoint : https://xxxxx.live.dynatrace.com/api/v2/otlp/v1/traces

      headers:

        api_token: <my token>

[Julius_Loman]

Most likely the permission scope for your API token is incorrect.  The API token must have  Ingest OpenTelemetry traces (openTelemetryTrace.ingest) scope at least.  Can you confirm that?