Magento – Magento 2.0.7 to 2.1 – Error in Review Order Page – “We cant place the order”

I was facing this problem on Magento 2, and realized it only happens when using Redis.

The problem was solved by increasing break_after_frontend from 5 to 15 in app/etc/env.php. I saw people struggling with the same problem on Magento 1, and the solution is quite much the same, but in app/etc/local.xml as described here.

Problem :"Asymmetric transaction rollback."

Solution :

1. Clear your cache by manually deleting the content of /var/cache/ folder , the var/page-cache/ folder and

= Magento 2.2.0 -> /generated/ folder < Magento 2.2.0 -> /var/generation/* folder

2. reindex your website by using the SSH command php bin/magento indexer:reindex

3. Make sure your website is in developer mode or in production mode and not in default mode'. You can check it by using the commandphp bin/magento deploy:mode:show. If it is indefault modeyou can change it toproduction or developer modeby using the commandphp bin/magento deploy:mode:set developerorphp bin/magento deploy:mode:set production`.

Before you use these commands clear your var/view_preprocessed folder and your pub/static folder also (afterwhich you need to recompile your pub/static folder with the command php bin/magento setup:static-content:deploy

Also be sure all your permissions of the folders are set like how Magento wants it more information on that here = Permissions