Server that your request has come is acting as a gateway or proxy to fulfill the request made by his client.
Web Browser => web customer => web background
This server (front-end Web) received an invalid response from an upstream (web background) server that has agreed to comply with the request.
In most cases, this does not mean that the server upstream is down, but rather that the server upstream and gateway / proxy do not agree on the protocol for data exchange.
This problem is most often caused when there is a problem with IP communications between the Web client and the back-end. Before attempting to solve this problem, you must disable the browser cache completely.
Our support team will be happy to help you solve this problem. Please contact our live support or respond to all entries you have received through technical for further assistance.