What happens when response fails to reach the clie

Question

This explains how token authentication works in rails when this lib is used.

But, if this (as shown in image below) happens, should I sign-in again to get a new valid token that can be used for the next request? This doesn't seem so good as network failure might often happen; isn't there a simple "RETRY" way?

EDIT: The server would accept the retry request, if it reaches within 5 seconds since the previous one, essentially treating it as a batch request. However, this wouldn't help solve my problem.