Fatal Error

Summary:

this is error is raised when i call the standard model 'Product'.

Fatal error: Call to a member function model() on null of type E_ERROR.

Content (required):

this is my code to call the model:

<?php

$result = $this->CI->model('Prodcat')->getPermissionedListSocialQuestionCreate(true);

echo $result;

?>

i write this code in my custom page in html tag <div>

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Code Snippet (add any code snippets that support your topic, if applicable):