Possible to disable dashboard access?

[pmpb]

Did you have any success?

EDIT:
I belive this is the answer:

Limit openHAB Cloud access

No. The Cloud Connector binding creates a proxy to OH’s REST API through myopenhab.org. You can control which of your Items get exposed to third-party services like Alexa and IFTTT. But the REST API is all or nothing.