OAuth2 issue / Mautic API

We are trying to update contact and company information via the Mautic API. With OAuth2 Authorization it is possible to get information for a contact, so OAuth2 seems to be working. But trying to edit a contact returns an error message:

{“errors”:[
{“code”:401,
“message”:“The response has unexpected status code (401).\n\nResponse: {“errors”:[{“message”:“API authorization denied.”,“code”:401,“type”:“access_denied”}]}”}],
“error”:{
“code”:401,
“message”:“The response has unexpected status code (401).\n\nResponse: {“errors”:[{“message”:“API authorization denied.”,“code”:401,“type”:“access_denied”}]}”}}

Both getting the contact information and editing the contact is working fine if we use HTTP Basic Authentification instead. Is it not possible to edit objects with the API and OAuth2?

For all who have the same issue:
it looks like that this is the solution: