Getting invalid date format while creating appointment

my request string is

{
“contact_id”: 3,
“description”: “test”,
“end_date”: “10/10/2019”,
“location”: “test”,
“remind_time”: 15,
“start_date”: “09/10/2019”,
“title”: “test”,
“user”: 1
}

response is

{
“message”: "Invalid date format “09/10/2019"”
}

please provide the solution asap

Some fields require certain formats. Date only fields I believe use the second one I mention below but you could try either and check.

YYYYMMDD

or

MM-DD-YYYY