401 Errors with AspNetCore API and Vue.js client

I’m using the Auth JS in my Vue client and attempting to secure my .NET Core API as well. Calls to my API are failing. I’ve ensured that both applications have the same issuer property set. Also, I’ve set the API up in the Authorization Server configuration area.

When using fiddler, I see the authorization fails for the following reason: WWW-Authenticate: Bearer error=“invalid_token”, error_description=“The signature key was not found”.

I have posted my access token into https://www.jsonwebtoken.io/ and it says that the signing key was verified.

Any thoughts?