joomla os membership Call to a member function getControlGroup() on null

On the url at:  careeractions.org/join-memberships

I have a situation where if a user clicks the signup button for a membership, they they get the following error (- while there is no error if the user is already logged into the front end of Joomla):

Call to a member function getControlGroup() on null

The info from the top of the error stack is:Call to a member function getControlGroup() on null
/home/career/public_html/components/com_osmembership/view/register/tmpl/default_form.php:87Call Stack#FunctionLocation1()JROOT/components/com_osmembership/view/register/tmpl/default_form.php:87
Thanks for help and guidance with this.

This has been solved. One of the fields did not have the proper access control level.

Great. Thanks for the update. I guess that's email field. You need to have it published and usually, Access Levels should be Public

Regards,

Tuan