You can increase the timeout of the login request to a connector. If you sign in to the admin UI and navigate to "Settings" and then "Connectors", you can modify either of these settings:"Connect timeout" "Read timeout"
The default value for these is 2 seconds.
There is more documentation on this topic here: https://fusionauth.io/docs/v1/tech/connectors/generic-connector/
You can also change them via the API, if that's more in line with your current workflow. That's documented here: https://fusionauth.io/docs/v1/tech/apis/connectors/generic/#update-the-generic-connector