Date issue in parameters in HTTP Request

I tried scraping few fields from web application to excel. One among is date of birth, created variable with data type as “System.DateTime”. While passing the same variable through parameters in http request, it is taking String as data type by default. I am getting invalid date format in attached screenshot.

I tried removing the variable from parameters in and created invoking new variable with data type as string, but still it i showing as string. I am unable to modify the data type over there. Could anyone help me here.

PFA of screenshots for reference.

DOB%20Error1

DOB%20Error