Kinds of system error
A system error can happen after stamping — for example outbound delivery failing while the CFDI is already issued. In that case, fix delivery; do not re-stamp.
What Lambda fixes itself
For some system stops, Lambda automatically recovers without changing what it already intended to stamp:- Work that was accepted but never started processing
- Mid-flight work that can safely continue the exact same attempt
- Limited retries when a stamp system error is known to be safe to retry