Error: The request includes no client credentials

[//]: # "Comment: facing below error while generating access token

Product/components used and version/fix level: API gw 10.1

Detailed explanation of the problem: When I try to generate the access token for oauth , I am getting below error

Error messages / full error message screenshot / log file:

Question related to a free trial, or to a production (customer) instance?

customer instance

The request body doesn’t contain client_secret.
Can you add and try?