I am definitely on the most current version.

I will try the verify rebuild utility tool and see if it helps.  Of course, I will have to do this individually for all 20 of my company files, so it'll take a while to see if it's the fix.

You have misunderstood my issue re: the payee name.  It has nothing to do with anything QB is filling in via a "rule".  Something in the functioning is messed up.  QB fills in the first name on the vendor list starting with the first letter I type and then SKIPS TO THE END of the vendor name as if I have accepted/pressed tab to select that vendor.  This doesn't happen 70% of the time.  It works just fine a lot, allowing me to type in the vendor name letter after letter until I enter or tab to accept that vendor name.  Then sometimes it freaks out and stops doing that. So 30% of the time it chooses the vendor for me, enters it completely, puts my cursor at the end of the name and I have delete all the incorrect letters type the next, then delete all the incorrect ones of the next vendor that happens to start with those 2 first letter, etc.  Or use the drop down menu exclusively to fill in my vendor.  Once I switch to another company file or close QB completely and reopen, it has usually fixed this and won't do it again for a while.