Getting 400 Bad request error on /token api after getting code from /authorize url

Here is the use case I have a sign-in widget which under the hood pointing to the okta portal. I want to create SSO for sub domain considering a security in point of view. So I have created sid which is stored in cooklie. Now the scenario is whenever there is active session I am calling /autorize api which returning 302 response and able to create code. Now this this code I am using to get accessToken and id_token But its returning following error. FYI, I am using okta-auth.js sdk and all api are invoked using the same sdk

: 
"invalid_grant"
error_description
: 
"PKCE verification failed."```

Hi @dnyaneshbhalerao! Are you manually making a call to the /token endpoint?