APM server not responding to OTLP

We have an Elastic server and an Elastic Agent (both 8.17.4) running on a Windows server.
An APM server is running within the Elastic Agent and there are a number of Fleet managed Elastic Agents running on other servers and they ingest data to the Windows server without problems.
I'm now trying to ingest data by sending OTLP/HTTP (protobuf) requests to port 8200 (HTTPS) of the Elastic Agent on the Windows server without luck.
When curling to port 8200 using "/v1/metrics" I get 404. In the Elastic Agent log I can see the call as a "http request" and it seems to be sent to the component "fleet-server"!?
Is there anything I have to do to enable OTLP in the APM server?
Do I need to install the "OpenTelemetry integration"?
Any hints are greatly appreciated!

Hey @Sven_Emtell ,

Do I need to install the "OpenTelemetry integration"?

To send to APM Server, you don't need to install anything. As long as the APM Server is running and correctly configured you should be able to ingest OTEL data.

Can you share the APM Server logs and the configuration?