En-/decryption fixed

backend/utils/userdata.js

@@ -0,0 +1,10 @@
+export const calculateAge = (birthdate) => {
+    const today = new Date();
+    const birthDate = new Date(birthdate);
+    let age = today.getFullYear() - birthDate.getFullYear();
+    const monthDiff = today.getMonth() - birthDate.getMonth();
+    if (monthDiff < 0 || (monthDiff === 0 && today.getDate() < birthDate.getDate())) {
+        age--;
+    }
+    return age;
+};