If you’ve double-checked all of your email management rules and still can’t figure out why incoming emails that don’t match your trigger rules are creating incidents, it is likely that you have the integration set to trigger generic incidents for anything that doesn’t match the rules you’ve configured.
After creating all of your email management rules, there’s an option at the very bottom of the page that says If an email does not match any of the rules above, XXX. You will want to set this to discard it. If you leave this to the default setting, then an incident will still be triggered even if it doesn’t match your trigger rules.