In documentation the life of the codes are given below
Life of Access Token
Access token once generated will survive for one hour.
Life of Authorization Code
Authorization token once generated will survive for 30 seconds.
What i observed
When i saw the json data related to access token, it has a field named expires_in:3600 which mean around 3.5 sec but in documentation it is specified as one hour. Coming to Authorization code, some times it is working when there is a delay between subsequent requests and sometimes it is failing, The user needs to Authorize again and again. So, Admin can you tell us what actually are the life times of Access Token and Authorization code