The 2 legged authentication php api you provided returning the "unauthorized_client". And i am not able to make it work. As per the suggestion related to the issue i switched to using 3 legged authentication. And the 3 legged authentication is processing up to getting username password. When i am entering the phone number and password which i used to login to my account It shows the error message "Phone number and password do not match. Please try again. Click here for more help or reset your password." I know the password is not wrong. But i can not get over this issue. Can you guide on me on this.