Having same problem, apologies if I am supposed to open new thread, please let me know in case.
Almost same error log as OP by mvstudio as you can see below.
Infos:
Running 1.5.6c (I know, will update as soon as possible)
Mid december there was a migration done by hosting company to new server, before that everything was working fine, meaning orders would get in after payment.
My question:
Can I apply the suggested changes (DrByte #12, and lat9 #16) as suggested?
Thank you
Happy 2021
[31-Dec-2020 20:38:25 Europe/London] Request URI: /index.php?main_page=checkout_process, IP address: xxx.xxx.xxx.xxx
#1 trigger_error() called at [/path-to/public_html/includes/classes/db/mysql/query_factory.php:171]
#2 queryFactory->show_error() called at [/path-to/public_html/includes/classes/db/mysql/query_factory.php:143]
#3 queryFactory->set_error() called at [/path-to/public_html/includes/classes/db/mysql/query_factory.php:270]
#4 queryFactory->Execute() called at [/path-to/public_html/includes/functions/functions_general.php:952]
#5 zen_db_perform() called at [/path-to/public_html/includes/classes/order.php:695]
#6 order->create() called at [/path-to/public_html/includes/modules/checkout_process.php:95]
#7 require(/path-to/public_html/includes/modules/checkout_process.php) called at [/path-to/public_html/includes/modules/pages/checkout_process/header_php.php:14]
#8 require(/path-to/public_html/includes/modules/pages/checkout_process/header_php.php) called at [/path-to/public_html/index.php:36]
--> PHP Fatal error: 1366:Incorrect integer value: '' for column tesoreri_zen156c.orders.delivery_address_format_id at row 1 :: INSERT INTO orders (customers_id, customers_name, customers_company, customers_street_address, customers_suburb, customers_city, customers_postcode, customers_state, customers_country, customers_telephone, customers_email_address, customers_address_format_id, delivery_name, delivery_company, delivery_street_address, delivery_suburb, delivery_city, delivery_postcode, delivery_state, delivery_country, delivery_address_format_id, billing_name, billing_company, billing_street_address, billing_suburb, billing_city, billing_postcode, billing_state, billing_country, billing_address_format_id, payment_method, payment_module_code, shipping_method, shipping_module_code, coupon_code, cc_type, cc_owner, cc_number, cc_expires, date_purchased, orders_status, order_total, order_tax, currency, currency_value, ip_address) VALUES ('100', 'NAME REMOVED', '', 'ADDRESS REMOVED', '', 'TOWN REMOVED', 'ZIP REMOVED', 'STATE REMOVED', 'COUNTRY REMOVED', 'PHONE REMOVED', 'MAIL REMOVED', '5', ' ', '', '', '', '', '', '', '', '', 'NAME REMOVED', '', 'ADDRESS REMOVED', '', 'TOWN REMOVED', 'ZIP REMOVED', 'STATE REMOVED', 'COUNTRY REMOVED', '5', 'PayPal', 'paypalwpp', 'free_free', 'free', '', '', '', '', '', now(), '2', '50', '0', 'EUR', '1.000000', 'xxx.xxx.xxx.xxx - xxx.xxx.xxx.xxx') ==> (as called by) /path-to/public_html/includes/functions/functions_general.php on line 952 <== in /path-to/public_html/includes/classes/db/mysql/query_factory.php on line 171.