Keep in mind that Reg E very VERY consumer friendly and rarely (if ever) requires "proof" from the customer. In that sense, it's really no different than a fraudulent dispute. They cancelled the service but is still posting to the account (not authorized). You can ask, but cannot require, your customer to contact the merchant, bring in proof, etc., but it's on you to determine that these transactions are valid. If you can't, then the normal Reg timelines, provisional credit, and closing apply.
Last edited by burkemi; 05/09/19 03:05 PM. Reason: Clarification
To the rest of your question - when it isn't a Reg E:
--I ordered "this" but haven't received it. It's an authorized transaction, so it's a merchant dispute.
--I didn't authorize this! But "this" is a free trial they signed up for and didn't cancel within the timeframe. You may still need to dispute under your card rules, but this isn't covered by Reg E.
--Recurring transactions your customer didn't cancel but wants to stop. Any transactions after that date are Reg E, any prior to are not.
Many many many other variables - but this is a few of the more common, in my experience anyway.
I reject your reality and replace it with my own.