Unified login and registration page, showing wrong form, if switched to other form and submitted with error

I was using logintoboggan, in one of our project,i enabled 'present unified login/registration page'
When i tried to login through 'user/login', then switched to registration form, filled the form with half email address and submitted form, after page reloads the error message shown, but form was login not registration form

Drupal version 7.41

Steps to recreate this issue

1. install logintoboggan
2. navigate to configuration -> system -> logintoboggan -> check the checkbox 'present unified login/registration page' and save the configuration
3. logout
4. navigate to user/login page
5. Page will be rendered with login form
6. Click "i want to create account"
7. type email as 'dd'
8. Click 'create account' button
9. page reloads with error message, but form is login fom not the registration form