Validity of the access token
The validity of an access token is 24 hours, and are refreshable up to 365 days. One needs to refresh them in order to avoid the Insufficient Privilege error.
How to refresh access token
Pass the access token in the query parameter and in the Authorization header, and then enter your public key. Please note that you need to enter the same public key used to create the access token.
Click here for the authorize endpoint documentation
And that's all! Hoped that helped!