When a row on the review screen looks wrong — a date a day off, an amount without its sign, a note that got cut — the fastest check is the source. Choose View original row on that row and a drawer opens beside the table with the exact line from your file, the column titles above it, and each column labelled with the field it fed: date, amount, note and so on.
Compare the two. If the file says one thing and the row says another, the cause is almost always the mapping — go back to Map columns and check the date format or amount layout. If the original row is not available, the file is longer than the preview holds; open it in a spreadsheet and look up the row number shown in the drawer.