IdentityServer - API - /connect/token endpoind returns erron unauthorized_client

I am trying to get token from ORIGAM IdenityServer via POST call on /connect/token endpoint. But I get an reponse like this

I log file I get such a message:

In appsettings.json acctually is directive AllowedGrantTypes, but question is if it is applied.

Is there something I do wrong?