Nostr: Why do features work in one Nostr client but not another?

Short answer

Clients choose which NIPs to implement and how to present them. A relay may also lack support for a requested feature or may reject events under its rules. Compare the client's feature list, relay capabilities, and the relevant NIP before assuming a bug. Your public key can travel between clients, but the interface and supported event kinds need not match.

Sources

Nostr Improvement Proposals index, NIP-11: Relay metadata.