Site Broke with Fatal error

Fatal error: Cannot redeclare custom_override_checkout_fields() (previously declared in /home/customer/www/abcd.com/public_html/wp-content/plugins/code-snippets/php/snippet-ops.php(469) : eval()’d code:4) in /home/customer/www/abcd.com/public_html/wp-content/plugins/code-snippets/php/snippet-ops.php(469) : eval()’d code on line 4

Hello,
Thank you for this very helpful plugin,
we had active some code successfully
However, after we enter a wrong code and run on our website,
the site broken, as shown above

We had restored the site and reinstall the plugin
the site still broken, we couldn’t use this plugin now,
we really want to use this plugin ,could you help us please,
Thank you !

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