Site locked after installing Contact Form 7 Signature Add-on

I have been working on building a new site for a few months now and am, literally, about 24 hours from finishing. I tried to install a plugin called “Contact Form 7 Signature Add-on” and everything crashed. Everything was fine prior to that so I know it was the cause. Problem is that now I cannot access anything to try and deactivate said plugin or anything else for that matter. To complicate things, I have my site visibility set to private because I wasn’t ready to launch.

I’m including the error message to see if anyone could PLEASE give me some direction. For the record the site is still okay from what I can see on the front end — I just cannot access anything at all as an admin.

Thank You!

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This is the warning message being thrown. I cannot get beyond it to deactivate and remove the plugin.

Warning: Use of undefined constant WPCF7_VERSION – assumed ‘WPCF7_VERSION’ (this will throw an Error in a future version of PHP) in /home/customer/www/healingriv.com/public_html/wp-content/plugins/contact-form-7-signature-addon/admin/class-wpcf7-signature-admin.php on line 215

Fatal error: Uncaught Error: Class ‘WPCF7_ContactForm’ not found in /home/customer/www/healingriv.com/public_html/wp-content/plugins/contact-form-7-signature-addon/admin/class-wpcf7-signature-admin.php:220 Stack trace: #0 /home/customer/www/healingriv.com/public_html/wp-includes/class-wp-hook.php(292): Wpcf7_Signature_Admin->remove_v3_js_callback(‘4.2.2’, ‘0’) #1 /home/customer/www/healingriv.com/public_html/wp-includes/class-wp-hook.php(316): WP_Hook->apply_filters(”, Array) #2 /home/customer/www/healingriv.com/public_html/wp-includes/plugin.php(484): WP_Hook->do_action(Array) #3 /home/customer/www/healingriv.com/public_html/wp-content/plugins/contact-form-7-signature-addon/includes/class-wpcf7-signature.php(294): do_action(‘wpcf7_signature…’, ‘4.2.2’, ‘0’) #4 /home/customer/www/healingriv.com/public_html/wp-includes/class-wp-hook.php(292): Wpcf7_Signature->wpcf7_signature_upgrade(”) #5 /home/customer/www/healingriv.com/public_html/wp-includes/class-wp-hook.php(316): WP_Hook->apply_filters(NULL, Array) #6 /home/custo in /home/customer/www/healingriv.com/public_html/wp-content/plugins/contact-form-7-signature-addon/admin/class-wpcf7-signature-admin.php on line 220

There has been a critical error on this website. Please check your site admin email inbox for instructions.

Note: The instructions didn’t resolve the issue. They referred to a “recovery mode” login which didn’t work.

WordPress version 5.7.2
Current theme: Bard (version 1.91)
Current plugin: Contact Form 7 Signature Addon (version 4.2.2)
PHP version 7.4.21

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