Прошу прощения, что сразу не выложил.
[Fri Apr 17 19:11:16.703716 2020] [lsapi:error] [pid 3173148:tid 139830293780224] [client 37.45.141.201:0] [host i-am-balloon.by] Backend fatal error: PHP Fatal error: Uncaught exception 'Exception' with message 'Error: EHLO not accepted from server!' in /home/rasek157/domains/i-am-balloon.by/public_html/system/library/mail.php:201\nStack trace:\n#0 /home/rasek157/domains/i-am-balloon.by/public_html/system/storage/modification/catalog/model/checkout/order.php(660): Mail->send()\n#1 [internal function]: ModelCheckoutOrder->addOrderHistory(100, '1')\n#2 /home/rasek157/domains/i-am-balloon.by/public_html/system/storage/modification/system/engine/loader.php(178): call_user_func_array(Array, Array)\n#3 [internal function]: Loader->{closure}(Array, Array)\n#4 /home/rasek157/domains/i-am-balloon.by/public_html/system/engine/proxy.php(25): call_user_func_array(Object(Closure), Array)\n#5 /home/rasek157/domains/i-am-balloon.by/public_html/catalog/controller/extension/payment/cod.php(17): Proxy->__call('addOrderHistory', Array)\n#6 /home/rasek157/domains/i-am-balloon.by/public_html/catalog/controller/extension/payment/cod.php(17): Proxy->addOrderHistory(100, '1')\n#7 [internal function]: Cont in /home/rasek157/domains/i-am-balloon.by/public_html/system/library/mail.php on line 201\n, referer: http://i-am-balloon.by/index.php?route=checkout/checkout
Вот такую информацию.
Я не модифицировал этот файл, поэтому и не понимаю в чем причина такого поведения