Hi Vignesh
In your date picker widget, you can go to the tab ‘Events’ and develop a validation flow on entering the date where you write the formatter yourself.
E.g., event on Enter: call a microflow, microflow PARSE_DateInputToCorrectFormat. If the ‘Invalid date’ error persist, do create this logic with a simple text input field.
Your third option is still entering the date in a correct way :)
Hope this helps!
Kind regards,
Leander