Timeout issue resolution when an instance fails

In the interaction scheme:

• the web application sends a request through a gateway + service discovery (GW+SD);
• the gateway redirects the request to one of the instances of users-api;
• the selected instance either hangs or does not respond within the allotted time (timeout).

It is required to describe an approach that allows providing the user with a correct response in case of a failure of an individual instance, despite the timeout.