Misleading error during 90-day password rotation: "old password incorrect" when new password fails policy

When signing in to AWS and being prompted to change an expired (or expiring) password due to the account's password rotation policy, the password change form returns the following error if the new password does not meet the account password policy:

"Your authentication information is incorrect. Please check your old password."

This error is misleading. The old password is correct — it was just used successfully to authenticate moments earlier on the same screen. The actual problem is that the new password fails one or more password policy requirements (e.g., minimum length, character classes, reuse prevention). Steps to reproduce:

Account has a strict password policy (e.g., min length 16, uppercase + lowercase + number + symbol, 90-day rotation, prevent reuse of last 5 passwords). IAM user signs in with their current password after the rotation period has elapsed. AWS prompts the user to set a new password, asking for the old password and a new password. User enters the correct old password and a new password that does not meet the policy (e.g., too short, missing a character class, or matches a recently used password). Form returns: "Your authentication information is incorrect. Please check your old password."

Expected behavior: The error should clearly state that the new password does not meet the account password policy, ideally specifying which requirement failed (length, character class, symbol set, reuse history, etc.). Actual behavior: The error blames the old password — even though it was just accepted by the same login flow seconds earlier. This sends users down a long debugging path, suspecting copy-paste issues, browser autofill, expired credentials, or admin-side problems, when the actual issue is purely on the new-password validation. Impact: This has been reported in various forms across re:Post and other forums for several years. It costs user time on every password rotation cycle and undermines trust in the error messaging during a security-sensitive flow. The fact that the old password was just used to authenticate makes the error particularly nonsensical. Request: Please update the validation logic on the password change form to surface a policy-specific error when the new password fails policy, distinct from old-password authentication failures. Ideally, the error should also indicate which specific policy requirement was not met.