Changed serialize_precision to -1

Same error, different mydebug.

Used the stored credit card in first attempt. OPC didn't like that without an additional refresh
Used the new credit card in 2nd attempt. "unchecked" save credit card and received error code 5

New MyDEBUG
Code:
[27-Apr-2020 13:05:35 America/Los_Angeles] Request URI: /index.php?main_page=checkout_process, IP address: 98.146.164.107
#1  trigger_error() called at [/home/WEBSERVERACCOUNT/public_html/includes/modules/payment/authorizenet_cim.php:447]
#2  authorizenet_cim->logError() called at [/home/WEBSERVERACCOUNT/public_html/includes/modules/payment/authorizenet_cim.php:1022]
#3  authorizenet_cim->chargeCustomerProfile() called at [/home/WEBSERVERACCOUNT/public_html/includes/modules/payment/authorizenet_cim.php:325]
#4  authorizenet_cim->before_process() called at [/home/WEBSERVERACCOUNT/public_html/includes/classes/payment.php:246]
#5  payment->before_process() called at [/home/WEBSERVERACCOUNT/public_html/includes/modules/checkout_process.php:92]
#6  require(/home/WEBSERVERACCOUNT/public_html/includes/modules/checkout_process.php) called at [/home/WEBSERVERACCOUNT/public_html/includes/modules/pages/checkout_process/header_php.php:14]
#7  require(/home/WEBSERVERACCOUNT/public_html/includes/modules/pages/checkout_process/header_php.php) called at [/home/WEBSERVERACCOUNT/public_html/index.php:36]
--> PHP Notice: Transaction Failed 
 Error code  : 5
 Error message : A valid amount is required.
 in /home/WEBSERVERACCOUNT/public_html/includes/modules/payment/authorizenet_cim.php on line 447.