@Paul-and-Dawn0 If you are working with the CSV converted to Excel, you should be able to fix the dates.
In Excel: Highlight the date column you want to work with. On the Home Ribbon, Number Section, select the dropdown arrow in the format box at the top of the Number section. Then go to the very bottom of the dropdown menu for More Numer Formats. Click.
A Format Cells box opens. On the Number tab, Category Box, select Date. Ignore the Sample and type option boxes as the CSV is using the short date format. Instead, go to the Locale (location) dropdown, and select English (United States) or English (United Kingdom). All of the dates should then convert to the format you have selected.
Good luck!