API not working for self-hosted instance

[BOHEUS]

Scenario:

1. Log in
2. Go to Settings
3. Toggle Advanced on
4. Go to API & Webhooks
5. Create new API key or use existing one
6. Copy API key and go here, select Localhost or other depending where self-hosted instance is located and paste the key

Actual: API is not working for self-hosted instance, when checking localhost:3000/graphql, GraphQL API says the token is invalid, REST API doesn't load at all

Expected: API must work for self-hosted instance

Note: In docs Core API doesn't load when token is invalid but Metadata API loads despite "wrong" token