I do not use Post Sale Management at all. In my closed auctions, I see the number 3 box is checked, indicating that I sent the buyer a "payment received" notice.
Anyway, I am not as concerned about that as I am the notation about a UPI Dispute?
Can someone please tell me what this is and how can I eliminate any post sale management activity in the future?
If your customer didn't pay you and you need to report it to eBay you can start a UPI Dispute (unpaid item dispute). It is an option that appears regardless, in post sale. If you aren't using post sale, just make sure that you have all post sale messaging turned off in your My Account section (click on the Post Sale Mgt. Options link).