I’m following Get an access token | Okta Developer and have completed the below steps successfully:
- Generated JSON Web Key Pairs Sets
 - Previous generated keys have been used to create a service thru the API
 - Access granted to okta.users.read scope
 - JWT string has been signed
 
and after that I’m getting the below error which says client_assertion_type is invalid
~  curl -X POST "https://dev-76039829.okta.com/oauth2/default/v1/token" \
    -H "Accept: application/json" \
-H "Content-Type: application/x-www-form-urlencoded" \
-d "grant_type=client_credentials \
&scope=okta.users.read \
&client_assertion_type=urn:ietf:params:oauth:client-assertion-type:jwt-bearer \
&client_assertion=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.......CsJGaHPEAP_iTitdeeBzi7uA4fluLZHJGVRWSn-JLEg"
{"error":"invalid_client","error_description":"The client_assertion_type is invalid."}%
I have checked the allowed client_assertion_type types, and looks correct, the only issue I noticed is that the Application the moment is created thru API doesn’t get a client secret assigned
Does anybody has any clue about what could be wrong?