NotProxy

Sign with the key or origin that owns the target object, then retry

The sender is not registered as a proxy for the account it tried to act for. Check the Proxies entry of the real account and confirm the sender appears there with a proxy type and delay compatible with the call.

Declared by the Proxy pallet; it classifies to the semantic code not_authorized.

Remediation

Sign with the key or origin that owns the target object, then retry

The same explanation is available in the terminal: btcli explain NotProxy.