confirmationPasswordYupFormik.js

const Schema = Yup.object().shape({
  password: Yup.string().required("This field is required"),
  changepassword: Yup.string().when("password", {
    is: val => (val && val.length > 0 ? true : false),
    then: Yup.string().oneOf(
      [Yup.ref("password")],
      "Both password need to be the same"
    )
  })
});