When I try to start a website from scratch (not using the demo import) going to user profile settings page in WordPress dashboard gives this error:

PHP Fatal error: Uncaught TypeError: Voxel\Membership\Base_Type::get_selected_plan(): Return value must be of type Voxel\Plan, null returned in /public_html/wp-content/themes/voxel/app/membership/base-type.php:125

Adding a if($membership) check in that line resolved the issue.