E0051

The event source refused the subscription's caller.

Check the refusal message and the source's access rules. An active API key or session does not replace application-level permissions. Ask the service owner to restore the required access, then subscribe again.

For Relay, select an enabled Dot agent and use a key with a grant for it. Grok agents use webhook delivery. Revoking its agent grant stops future event delivery without revoking the key itself.