Invalid
Exception thrown when the challenge transaction memo value doesn't match expected value.
SEP-10 Requirement: If the client provided a memo when requesting the challenge, the returned challenge transaction MUST contain that same memo value.
This validation ensures:
The server correctly preserved the requested memo
The challenge is for the correct sub-account
Protection against memo substitution attacks
Memo values are used to identify sub-accounts in scenarios where multiple users share a single Stellar account (common for custodial services).
Parameters
expected
The memo value the client requested
actual
The memo value found in the challenge transaction