Use The KYC iFrame

var myAppId = "{your-app-id}";
        var environment = "stage"
        var apiVersion = "3.0";
        var error = WePay.configure(environment, myAppId, apiVersion);
            if (error) {
                console.log(error);
            }

        var iframe_container_id = "kyc-iframe";
        var options = "";
        var country = 'US'; // ['US', 'CA']  --> This is the country the merchant is based in, which your platform previously collected.
        var ssn4_enabled = true; // ['false'] --> Note that some situations may still require SSN9 from the merchant.
        var kycIframe = WePay.createKycIframe(iframe_container_id, { country_code: country.toUpperCase(), ssn4_enabled: ssn4_enabled });
        if (kycIframe.error_code){
            console.log('The kyc iframe has not been created, due to container id or country_code error.');
            console.log('error', kycIframe);
        }
        document.getElementById('submit-kyc-button').addEventListener('click', function (event) {
            var ein = document.getElementById('text-input-business_ein')
            console.log(ein);
            kycIframe.tokenize()
                .then(function (response) {
                   console.log('response', JSON.stringify(response));
                   var node = document.createElement('div');
                    node.innerHTML = JSON.stringify(response);
                    })
                .catch(function (error) {
                    console.log('error', error);
                    var node = document.createElement('div');
                    node.innerHTML = JSON.stringify(error);
                });
        });