Sorry, but something went wrong. Please contact the seller. Issue : when checkout with credit card (Authorized.net) - Magento-2.1.2

I've also experienced the same issue in Magento ver 2.1.2 Opensource. It was due to payment transaction is to long and exceeded the timeout which is 30sec. In my case I've increased the timeout time to 60sec in

Magento\Payment\Model\IframeConfigProvider::TIMEOUT_TIME