This was my hosting companies response:
There I see a number of errors in both your HTTP and HTTPS PHP Script Error Logs referring to a few deprecated features, and one of the errors references your contactus.php script, for example:
[03-Jan-2022 10:28:49 EST5EDT] PHP Fatal error: Uncaught Error: Call to undefined function split() in /big/dom/xprolectricllc/www/WA_ValidationToolkit/WAVT_Scripts_PHP.php:327
#0 /big/dom/xprolectricllc/www/contactus.php(15): WAValidateEM('kathy@kathybank...', true, 2)
thrown in /big/dom/xprolectricllc/www/WA_ValidationToolkit/WAVT_Scripts_PHP.php on line 327
So, my guess is that you will either need to downgrade the version of PHP you are running to accommodate the deprecated script language in your contact form (you are currently running PHP 7.3.3), or you will need to update the syntax in your contact form so that it can function with the current version of PHP you are running.