diff --git a/web/src/auth/SignupPage.js b/web/src/auth/SignupPage.js
index 2b43b87f..b3bc3353 100644
--- a/web/src/auth/SignupPage.js
+++ b/web/src/auth/SignupPage.js
@@ -182,6 +182,8 @@ class SignupPage extends React.Component {
     AuthBackend.signup(values)
       .then((res) => {
         if (res.status === "ok") {
+          // the user's id will be returned by `signup()`, if user signup by phone, the `username` in `values` is undefined.
+          values.username = res.data.split("/")[1];
           if (Setting.hasPromptPage(application) && (!values.plan || !values.pricing)) {
             AuthBackend.getAccount("")
               .then((res) => {