put https://app.peopleforce.io/api/public/v2/employees/
Update an employee
Custom Fields
You can update employee custom fields by using the generated "internal_name" of the employee field that you have in PeopleForce. This unique field name is automatically generated when you create a custom field, and is returned by the GET /employee_fields endpoint.
For example if you have a field labelled "Tax number" in PeopleForce,it will autogenerated an internal name called "tax_number", you can then use within your request along with other system attributes of the employee, for example "first_name"
{
"first_name": "Andrew",
"tax_number": "123123"
}