Help understanding fatal error

Hello,

I am trying to get my blog running again on WordPress and am getting this fatal error when I try to update my theme on WordPress. Any theme I try to use causes this error. I am not very knowledgable and hope that I posted this in the right place to get some help. Any help or guidance would be greatly appreciated. 🙂

“ContentUnlockedFitness

Fatal error: Uncaught Error: Cannot use object of type WP_Error as array in /home/buddhab6/public_html/wp-content/plugins/content-unlocked-fitness/contentunlockedfitness.class.php:56 Stack trace: #0 /home/buddhab6/public_html/wp-includes/class-wp-widget.php(519): ContentUnlockedFitness->form(Array) #1 /home/buddhab6/public_html/wp-admin/includes/widgets.php(276): WP_Widget->form_callback(Array) #2 /home/buddhab6/public_html/wp-includes/class-wp-customize-widgets.php(1053): wp_widget_control(Array, Array) #3 /home/buddhab6/public_html/wp-includes/class-wp-customize-widgets.php(1001): WP_Customize_Widgets->get_widget_control(Array) #4 /home/buddhab6/public_html/wp-includes/class-wp-customize-widgets.php(690): WP_Customize_Widgets->get_available_widgets() #5 /home/buddhab6/public_html/wp-includes/class-wp-hook.php(287): WP_Customize_Widgets->enqueue_scripts(”) #6 /home/buddhab6/public_html/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array) #7 /home/buddhab6/public_html/wp-includes/plugin.php(478): WP_Ho in /home/buddhab6/public_html/wp-content/plugins/content-unlocked-fitness/contentunlockedfitness.class.php on line 56
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