Error after install

After installing, I can activate the theme. But when I click on Theme Options, I get this:

Fatal error: Call to undefined method stdClass::add_help_tab() in /home/content/92/7956392/html/testing-site/wp-content/themes/themeforest-3649588-aqua-responsive-multipurpose-wordpress-template/Aqua/option-tree/includes/ot-settings-api.php on line 180

When I click on Customize I get this: Cannot load customize.php.

I tried re-uploading the theme files with the same result.

Can you tell me the problem?