From the error code it seems there is access issue. have you also included Ingest Metrics v2, Read metrics v2, Ingest events v2 & Ingest logs v2 along with opentelementary in scope.
If not create new with all enabled and see if it is accessible.
i did try but the same error occurred. I used to follow the same steps given by you. I am using the access token. any following the step that i am using please check this are correct ..