Hello @Abhinav Shrivastava - The error doesn't appear to be coming from the API Management service, this may be a config issue with your AAD app.
Please review the answer on the link below and change the grant type of your AAD app to Authorization Code
flow, and try to call the REST API again:
https://learn.microsoft.com/en-us/answers/questions/537694/cross-origin-token-redemption-is-permitted-only-fo.html