I am having trouble with Account linking. The scenario that happens is I am able to link my account successfully and utilize my skill correctly and see the accessToken in the input JSON, but once the expire_in time passes and I try to invoke my skill I score an input JSON with no accessToken parameter even though on our Auth server creates a current token. The next is more confusing because if I invoke the skill again immediately after I score an input JSON with the current accessToken parameter that was generated. For some reason it seems to be lost in the Amazon service between getting the current token and passing it as a parameter in the input JSON
Source: amazon.com