The generate session is not working
PM_MERCHANT_AUTH_400670 error code is sent in case there are some in case parameters or headers sent in the request are invalid or missing.
It would be really helpful if you could share the cURL for the request that you sent so that we can debug it further.
If you are using our Sdk client, please make sure that you are passing the correct request token while calling generate session method
PMClient pmClient = new PMClient("your_api_key", "your_api_secret");
Thank you, some issue with my parameter entry