Error 425 Too Early. Typically, you could never need to manage this status code as an developer, except if you are making HTTP(s) servers from scratch.
The server is unwilling to risk processing a request that might be replayed.
Step 1: Intermediaries May Consequently Retry The Request
Intermediaries that receive this error, it MAY be consequently retry the request after permitting the handshake to finish except if the first request contained the Early-Data header field when it was gotten.
Step 2: Client Must Consequently Retry The Request
Clients that send the request in early data MUST consequently retry the request. Such retries MUST NOT be sent in early data.