At the moment we develop a smart home skill (Skill ID: amzn1.ask.skill.41a6b24a-cad4-4eab-bea2-292edc822fb7) and we have a single user that can not activate the Skill. He recently deactivated the skill and wanted to activate it again but can't get past the account linking.
I use a API gateway HTTP proxy to see what is happening while the account linking is in progress, I can see that the Authorization URI is requested and after that a Access Token is requested too and send back.
Account linking still fails for this user.
I tried this myself but could not reproduce this in any way, someone has made such an experience too?