Why am i having errors passing a screen date field into other variables defined as dates ?

I have a line in my c# application where i pass a Date variable into my model and a defined static class variable (see below)

EmployeeDetails.staticbirthdate = model.birth_dt = Convert.ToDateTime(BirthDateValue.Text);

The Birthdate  on screen reads  28-07-2019 (see  screen below)


When passing the date variable to both the model and static class variable which are both defined as date

the values now read 0001/01/01 and not the actual value on screen and i end up with an error

while still trying  to read the date field into those variables.

See Error scree below


The line being flagged above is part the definition below

{
            PersonnelModel model = new PersonnelModel();
            EmployeeDetails.staticstaffno = model.type_app = TypeAppValue.Text;
            EmployeeDetails.staticstaffno = model.staff_no = StaffNoValue.Text;
            EmployeeDetails.staticsurname = model.surname = SurnameValue.Text;
            EmployeeDetails.staticfirstname = model.firname = FirstNameValue.Text;
            EmployeeDetails.staticmidinit = model.midinit = MidInitValue.Text;
            EmployeeDetails.staticaddressline1 = model.home_add = AddressLine1Value.Text;
            EmployeeDetails.staticaddressline2 = model.home_add2 = AddressLine2Value.Text;
            EmployeeDetails.staticaddressline3 = model.home_twn = AddressLine3Value.Text;
            EmployeeDetails.staticphoneno = model.offic_phn = PhoneNoValue.Text;
            EmployeeDetails.staticbirthdate = model.birth_dt = Convert.ToDateTime(BirthDateValue.Text);
            EmployeeDetails.staticemployeddate = model.empl_dt = Convert.ToDateTime(EmployedDateValue.Text);
            EmployeeDetails.staticstaffstatus = model.salesstaff= SalesStaffValue.Text;
}

Select allOpen in new window

What is wrong with the way i have passed the date field and how do I resolve this error ?

Thanks  

Olukay