consider the following code:

const handleEmployeeNumberChange = async (e, value, name) => {
        if (name === 'Employee Number') {
            const employee = await employeeServices.getByNumber(value);
            formik.setFieldValue('Employee Name', employee['Personal Information']['Employee Name']);
            formik.setFieldValue('Designation', employee.Company.Designation);
            console.log(employee.Company.Designation);
            formik.setFieldValue('Department', employee.Company.Department);
            const element = { target: { name, value } };
            formik.handleChange(element);
        }
    };

Some useful information:
The setFieldValue for the Department is working as expected, but not working for Designation. it is setting "" as the value, I logged the value of employee.Company.Designation and it is what is expected. I will post a small clip below for more clarity:

https://imgur.com/a/6Oduo7Z