I see. I tested the sort in Inbox, and found it sorts by what it appears in there (the instance name). Also if the date is in word (like april, may...) it sort by the letter; April comes before January. Is this right?
Above, I sorted descending
Yes that is correct, it sorts alphabetically, not by the data in your records.
If you want to sort by date you could potentially format the date in your instance name to be dd/mm/yyyy