@lubos, when I logged in and opened the business, everything seemed fine. The summary screen was resolved. But, I re-ran the same edit prcocess, I did yesterday i.e.edit of an item in chart of account (see attached picture below). The problem came back with same internal error.
I am not sure if this problem came back due to edit of the same item (head) in chart of account or does happen with other items (heads) in chart of account. To make sure, I am downloading a back up file then I will revert after I have done a check