Getting access accept message from radius server but our client is considering the message as a authentication failure, what may be the cause, suspecting issue with Authenticator value which receiving in response from server, hope password may be not wrong as client getting Access-accept(2). How to check authenticator is correct or not. client works on RFC2865

Expecting a python script or manual procedure to calculate the Authenticator value, tried multiple ways to calculate but value not matching for successful trace also.